Welcome to the Huberman Lab Podcast,

where we discuss science

and science-based tools for everyday life.

I’m Andrew Huberman,

and I’m a professor of neurobiology and ophthalmology

at Stanford School of Medicine.

Today, we’re discussing water.

Now, to some of you, water might seem like a boring topic,

but I assure you that water is anything but a boring topic.

In fact, water as a substance is incredibly interesting

for a variety of reasons that I’ll explain today.

In fact, we are going to discuss

the physics and chemistry of water,

and I promise to make it accessible to anyone and everyone,

regardless of whether or not

you have a physics or chemistry background.

And I will discuss how your body needs and utilizes water,

depending on what type of water you drink,

the temperature of that water, when you drink the water,

and indeed, how you drink that water.

Now, water is actually a pretty controversial topic.

In fact, in preparing for this episode,

which took me several months, in fact,

I ran into highly contradictory information

and had to go on some real deep dives

in order to ferret out

the best and most accurate knowledge for you.

I also found that there are generally

two camps of people out there

in terms of how they think about water

and the consumption of water.

One camp, generally speaking,

is of the mind that tap water is completely safe.

Perhaps it needs a little bit of filtering,

but that in most areas of the world,

if it runs out of the tap,

and unless there’s a warning sign directly above the faucet,

that you can drink the tap water.

The other camp seems to be the camp

that does not trust anything that comes out of the tap

and is excited by, and in fact, relies on things

like reverse osmosis, deuterium depleted,

hydrogen rich, or other forms of water

that sometimes can be very expensive

or at least involve some substantial steps

in order to clean, filter, alter the chemistry of,

or in some other way adjust

before they are willing to consume it.

So today, what we’re going to try and do

is to address all the stances around water.

For instance, we will discuss whether or not

tap water is indeed safe,

and I will give you some tools that will allow you

to address whether or not

the water coming out of your tap is safe,

as well as some tools that will allow you to address

how to clean that water

if indeed it does need filtering and cleaning,

in particular for things like fluorides

and endocrine disruptors,

which it turns out are quite prominent in a lot,

not all, but a lot of tap water sources.

I will also talk about the more, quote unquote,

esoteric forms of water that I mentioned a few minutes ago.

So I will go systematically through the list

of distilled, reverse osmosis, spring water,

deuterium depleted water, high pH water.

And for those of you that are already screaming out

as you hear this, oh no,

he’s going to tell us that pH water

can alter the pH of our body in helpful ways.

I’m not going to tell you that,

but I will tell you that the alkalinity

or acidity of the water,

that is the pH of the water that you drink,

has a profound impact on your ability

to absorb and utilize that water

and the impact that those water molecules have

on specific biological systems.

So it turns out pH is very important,

but not for the reasons

that you’ve probably heard about previously.

I will talk about how the temperature of water

that you drink does indeed turn out to be important

for the rate of absorption of that water

and its impact on the cells, tissues,

and organs of your body and thereby your health.

And I will talk about various zero cost

and low cost tools that you can use

in order to get the most out of the water that you drink.

And finally, I will talk about

when and how to hydrate your body best.

Before we dive into today’s topic,

I want to share with you some very interesting results

that were just published

on the use of deliberate cold exposure to benefit fat loss.

Now, deliberate cold exposure is a topic

I’ve covered before on this podcast.

We have an entire episode about that

that I’ve linked in the show note captions.

Deliberate cold exposure can be done by way of cold showers

or immersion in cold or ice water up to the neck.

And that’s typically the ways that it’s done.

It has been shown to reduce inflammation,

to increase metabolism.

And I think some of the most exciting results

that have been published are the results,

certainly in humans,

showing that deliberate cold exposure

can increase the release of so-called catecholamines,

which are dopamine, norepinephrine, and epinephrine.

And those increases in those three molecules

are quite long lasting and lead to substantial increases

in mood and focus throughout the day.

Now, many people out there

hear about deliberate cold exposure and cringe.

Other people hear about it and cringe

because they’ve heard that deliberate cold exposure,

especially by way of immersion in water,

can block the adaptation to strength or hypertrophy training.

What I mean by that is yes, indeed,

there are data showing that if one gets into very cold water

up to the neck in the six hours, anytime that is,

in the six hours after strength or hypertrophy training,

that some of the strength and hypertrophy increases

that one would observe are blocked

by that deliberate cold exposure.

However, after six hours does not seem to be a problem.

So it can be done on other days

besides the strength and hypertrophy training.

It can be done before strength and hypertrophy training.

It can be done after endurance work.

And I should mention that it does not appear

that cold showers disrupt the adaptations

to strength and hypertrophy training,

even if they are done immediately

after strength or hypertrophy training.

Okay, with that said,

many people do enjoy the effects of deliberate cold exposure,

in particular for those increases in mood and alertness

that are the consequence of those increases

in the catecholamines, dopamine,

norepinephrine, and epinephrine.

And again, those increases are very long lasting.

So it’s not just during the exposure to cold,

it is for several hours, up to four,

maybe even five or six hours,

depending on how cold

and how long the deliberate cold exposure happens to be.

Again, there’s a lot to say

and explore about deliberate cold exposure.

So again, I’ll just refer you to the episode

on deliberate cold exposure.

If you want to explore the mechanisms

and the positive health outcomes,

some of the controversies within the data, et cetera,

within that episode.

Meanwhile, I definitely want to share with you

the results of this recent study that just came out.

The title of this study is

Impact of Cold Exposure on Life Satisfaction

and Physical Composition of Soldiers.

The reason this study is very interesting

is that it’s one of the few studies that used,

I should say explored both deliberate cold exposure

by immersion in cold water,

as well as deliberate cold exposure by way of cold showers

as it relates to weight loss.

Now there’s already data out there

on the effects of deliberate cold exposure and metabolism.

And here I’m mainly referring to the beautiful work

of Dr. Susanna Soberg and colleagues in Scandinavia

that showed that people that do 11 minutes total

of deliberate cold exposure by immersion in cold water

up to the neck per week.

So 11 minutes per week total

spread out across some different sessions

by way of getting into water

that’s uncomfortably cold up to the neck

and then getting out

and then doing that several times per week

to hit that 11 minutes or more threshold.

And this is very important.

We’ll come up in a moment in the context of this new study

and warming up not by getting into a warm shower,

which is frankly what I do after my cold showers

or getting into the ice bath or cold water immersion,

but rather forcing their body to warm up naturally

by using its own metabolic abilities.

In those studies,

they observed substantial increases in brown fat stores,

which are fat stores that you really want

around the heart and clavicles,

increases in metabolism that were quite dramatic,

in my opinion,

and that could be very beneficial

for allowing people to feel more comfortable

at cold temperatures when they’re not in cold water

and on and on.

So lots of benefits shown in that study.

In this study,

what I thought was particularly interesting is again,

they explored both immersion in cold water

and cold showers and the duration of cold exposure

that they found led to substantial fat loss,

especially around the abdomen

was very brief deliberate cold exposure.

Let me give you a few details about this study.

The study involved 49 subjects

that include both males and females.

This is also really important.

The beautiful work of Susanna Soberg and colleagues,

as far as I know,

only looked at males.

This study looked at males and females.

They were 19 to 30 years old

and there basically were two groups.

People either were assigned to get deliberate cold exposure

or they were not assigned to deliberate cold exposure.

The form of deliberate cold exposure

involved one session per week of cold immersion

in cold water up to the neck.

And to just give you a sense of how cold it was,

it was three degrees Celsius,

which translates to about 37 and a half degrees Fahrenheit.

That’s pretty darn cold,

but it was only for two minutes.

So one session at three degrees Celsius,

otherwise known as 37.4 degrees Fahrenheit

for two minutes every week, once a week.

In addition, the same subjects

did five cold showers per week

or a minimum of five cold showers per week.

And those cold showers were slightly warmer

than the immersion in cold water condition.

So they were 10 degrees Celsius approximately

or 50 degrees Fahrenheit, still pretty cold.

And the duration of that cold water exposure in the shower

was just for 30 seconds.

Okay, so this is interesting to me

because many people don’t have access

to cold water immersion.

They might not have an ice bath or any place they can do that

but most people do have access

to a cold shower of some sort.

Plus, I think most people could do

probably one ice bath per week

or find a place where they could get

into cold water safely.

Now I should point out that some people

will not do well going into 37.5 degree Fahrenheit,

AKA three degrees Celsius water,

having never done anything like this before.

So if you’re going to try and employ

these sorts of protocols that were used in the study,

I do recommend that you ease into it

over the course of a week or so

and become somewhat adapted

to the shock of cold water exposure.

So maybe start at 50 degrees Fahrenheit,

kind of ease your way back

in terms of the cold water immersion especially.

Now, another critical feature of this study

is as with the beautiful work by Susanna Soberg,

the subjects were told to warm up naturally

after the deliberate cold exposure.

So they basically hung out

outside of the cold water immersion

or outside of the cold shower for 10 minutes

after they were exposed to the cold

in their bathing suit

or I’m assuming they were wearing something.

But the point is that you are not going

from deliberate cold exposure directly into a hot shower

or a sauna or something of that sort.

So again, their bodies were forced to heat up again,

naturally after the deliberate cold exposure,

but after the 10 minute period,

they were able to do whatever they wanted essentially,

reclothe, take a warm shower and so on

and go about their day.

Now, the results of this deliberate cold exposure protocol,

again, two minutes in cold immersion

at three degrees Celsius, 37.5 degrees Fahrenheit

plus five cold showers per week of two minutes long,

a little bit warmer,

10 degrees Celsius, 50 degrees Fahrenheit.

Now, the deliberate cold exposure used in this study

caused many different statistically

significant positive changes.

They had a very extensive questionnaire

that related to mood,

everything from levels of anxiety to sexual satisfaction

and on and on.

In fact, they saw a statistically significant improvement

in sexual satisfaction

in the subjects that were exposed to deliberate cold exposure

not in the control group.

Although they didn’t look at this,

chances are those improvements in sexual satisfaction

were the downstream consequence of the known increases

in testosterone and free testosterone

that occur in both men and women

who do this sorts of deliberate cold exposure.

Again, testosterone being an important hormone

for libido in both men and women.

They also saw improvements in regulation of anxiety,

which I think is very interesting,

given that the deliberate cold exposure

often causes people anxiety,

but here and in other studies,

we’ve seen it can lead to a better ability

to buffer against anxiety

in the normal happenings of everyday life.

Perhaps the most interesting and significant results

that they found in the study, however,

were that in particular in men,

there was a reduction in waist circumference

following eight weeks of this deliberate cold exposure,

as well as a 5.5% on average,

5.5% reduction in abdominal fat

that was quite statistically significant

when compared to the other groups.

Now, why there was no observed reduction in abdominal fat

or waist circumference in the female subjects isn’t clear,

could have to do with just the way

that body fat is stored and metabolized

in females versus males.

That is going to be a topic for future exploration.

So I do think this study is very interesting

because when you look at the landscape of science

and discussion around deliberate cold exposure,

I think there’s a general consensus now

that deliberate cold exposure

can change one’s sense of mood and wellbeing

through the increases in catecholamines

that I mentioned earlier.

But the impact on metabolism itself

has been somewhat controversial

because the overall changes in metabolism

that are observed while statistically significant

in many studies have not ever really been shown

to translate into weight loss or body fat loss

in any kind of specific way.

And of course, a great advantage of this study

is that by exploring soldiers,

they were able to really hold constant

a number of other features,

like the amount of daily activity

that those soldiers are exposed to,

their diet, their living conditions,

and so on and so forth.

So at least insofar as human studies are done,

it’s a very well-controlled study.

We’ll provide a link to the study in the show note captions.

And for those of you that are thinking

about employing the protocol

that’s used in this particular paper

or combining it with existing

deliberate cold exposure protocols,

to me, it seems pretty straightforward

and a pretty minimal time investment,

just two minutes of deliberate cold exposure

by way of water immersion up to the neck

and five times a week of 30 seconds each

of deliberate cold exposure by way of cold shower.

And just a quick mention about cold showers,

if you’re going to use cold showers

to do deliberate cold exposure,

you’re going to want to stand under the shower itself,

and essentially have it hit your head,

the back of your neck and your upper back,

which is where most of your brown fat stores

are concentrated.

It turns out that cold exposure

to those regions of the body in particular

are going to trigger the adaptation

of increased brown fat stores,

which involves increases in mitochondria in those fat.

Again, this is not the blubbery fat beneath the skin.

This is the fat that acts as kind of an oil in the furnace

that is your thermogenic properties of your body

to generate heat and burn off

so-called white adipose tissue elsewhere in the body.

Now, anyone that understands the laws of physics

and thermodynamics will be saying,

wait, in order to get fat loss,

you need to have a caloric deficit.

Calories in, calories out still applies.

And yes, that’s absolutely true.

We can only conclude on the basis of the results

of this study that the people that lost body fat

were indeed in a caloric deficit,

presumably because all other factors

were held more or less constant in this group of soldiers,

presumably because the deliberate cold exposure itself

elevated metabolism,

thereby increasing the calories out component

of the calories in, calories out equation,

which of course governs the rules of weight loss

and body fat loss as well.

Before we begin, I’d like to emphasize

this podcast is separate from my teaching

and research roles at Stanford.

It is however, part of my desire and effort

to bring zero cost to consumer information

about science and science-related tools

to the general public.

In keeping with that theme,

I’d like to thank the sponsors of today’s podcast.

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Let’s talk about water,

and let’s start off by answering the question,

what is water?

Water is of course H2O.

Most everybody knows that from an early age,

but what H2O means is that each molecule of water

consists of two hydrogens and one oxygen.

Now the physical arrangement of those two hydrogens

and one oxygen turns out to be really important

for how water functions in the body

and frankly elsewhere in our world and life.

If you were to make a peace symbol,

that is to put up your index finger

and your middle finger simultaneously,

in fact, I’m going to recommend you do that now,

unless you’re using your hands for something else important,

in which case do it later.

Well, if you make that peace symbol

and you look at your hand,

you have a pretty good impression

of what an individual water molecule consists of,

which is H2O, two hydrogens and an oxygen.

And with that peace symbol,

the fingers or the tips of your fingers rather

are going to represent the hydrogens.

Your fingers, that is the length of each of those fingers

is going to represent the electron bonds to the oxygen

and the palm of your hand

and the fingers that are down

are going to represent the oxygen, okay?

Now, what’s important about that visual impression

or visual image of the individual water molecule

is that it is polarized.

That is the hydrogens over on one side,

both of them are over on one side

and the oxygen is over on another.

And what’s really important about water molecules

being polarized is that they can bind to one another

by way of that polarization.

And this has to do with something

that we all kind of learned in chemistry at one point,

but many of us forgot.

Maybe we didn’t even understand it the first time around,

which is that positives and negatives attract.

So when you have individual water molecules,

they have the opportunity to interact

and essentially bind to one another.

And they bind through what are called covalent bonds.

Covalent bonds are relatively weak bonds.

And so as a consequence, water can change its conformation.

However, covalent bonds are strong enough

that water actually can maintain some structure

and that structure will vary, of course,

depending on its temperature.

So what you need to know about water is that indeed,

it consists of lots of individual H2Os

and those H2Os can arrange themselves in different ways.

And that temperature is a strong determinant

of the arrangement of those water molecules.

That is, they’re bonding to one another.

And in fact, even they’re spacing between those bonds.

So again, even if you don’t have any chemistry,

stay with me because you’ll definitely understand this.

Water can exist in at least three forms

and maybe four forms.

We know that it can be liquid, of course.

That’s really normally what we think of

when we think of water.

It can be gas, so we think of steam, right?

So if you heat it up, it takes on a,

not a semi-solid or a semi-liquid form.

It takes on this property of steam or gas, okay?

So when you see steam or when you breathe on a cold day

through your mouth or through your nose

and you see your air,

those are water molecules that are condensing,

that is bonding in certain ways

based on differences in temperature

between the inside of your body and the outside air.

And of course it can be a solid, it can be ice.

Now, ice is fascinating and important

in understanding how water works.

And this will become relevant later

when we think about how water works within the body as well,

especially how different temperatures of water

impact the health and behavior of our cells.

And the most important point to understand

about water in its solid state

is that unlike most substances,

when water is in its solid state,

it is actually less dense than when it’s in its liquid state.

So just think about that.

Most substances, like most metals for instance,

when they are in a solid state,

they’re more dense than when they’re in a liquid state.

So for instance, if they’re in a solid state,

they will sink in a container filled with their liquid form,

not water.

Water is very interesting because as you cool water

and water transitions from a liquid to a solid,

it still binds.

That is, it could form bonds

between those different molecules of water,

but the spacing between those H2Os,

so again, those peace symbols with hands,

if you had a bunch of those,

if you had a thousand hands all making peace symbols,

they can bond to one another.

But when it’s cold,

those bonds are actually made further apart

from one another.

As a consequence, ice, as we all know, floats in water.

In other words, put very simply,

water is unusual and special in that in its solid form,

ice, it is actually less dense

than when it’s in its liquid form.

And that’s why ice floats in water.

Now this is important, not just to our biology,

but to all of life.

Because if you think about it,

if it were not the case that water is less dense

in its solid form, ice, than it is in its liquid form,

the bottoms of our oceans

would be covered with thick sheets of ice.

And if that were the case,

you can be absolutely sure

that life would not exist on our planet the way that it does

and there’s a good chance

that we would not exist as a species

because so much of what allows us to exist on this planet

and the other animals to exist on this planet

relies on photosynthesis pathways

and plants that are dependent on the sun

and interactions with the oceans and lakes

and other bodies of water.

And of course, the ice caps are vitally important.

That is the presence of ice, especially at the poles,

but elsewhere in bodies of water as well.

So called icebergs are a critical part of the ecosystem

that allows for everything from photosynthesis

to the ability of certain animals

to extract food from each other

and from their local resources.

Now there’s a whole discussion to be had there,

but the important point for now

is that the physical properties of the bonds between water

that are made and changed depending on temperature

turn out to be essential

for us to be present on this planet at all

and for our cells to function in the ways that they do

for sake of health and for sake of disease.

And we’ll explore this later

when we talk about the critical relationship

between temperature, pH,

which is the relationship between alkalinity, how basic,

or acidity, how acid a given liquid,

or in this case, we’re gonna be talking about water is,

and the ways that our cells can or can’t use water.

So I realized that this is a fairly in-depth

for those of you that don’t have much of a background

in chemistry.

I’ve tried to keep it really top contour,

but if you can make a peace symbol

or if you can just imagine a peace symbol in your mind

and realize that that’s a water molecule

and that those water molecules can bind to one another

through bonds that are relatively strong,

but weak enough that they can be broken if they need to,

and that the temperature

that those water molecules are exposed to

changes the distance between those bonds,

and that’s what allows ice to float in water,

then you are gonna have no problem

with the remainder of the discussion today.

In fact, you will also have the ability

to understand things that you’ve observed many times over,

but perhaps have never thought about

or really understood, which are, for instance,

that water has a certain level of surface tension.

For instance, if you’ve ever been to the ocean

and the waves are coming in,

what you’ll notice is if you walk on the dry sand

or gravel, pebbles, that is, of the ocean,

it’s very easy, right?

I mean, the pebbles move down or the sand moves down,

it depresses a little bit due to the weight of your body,

but as you get closer to the water,

you’re gonna sink deeper

because that sand is more saturated with water,

but at some point,

you won’t be able to actually walk on top of the water,

right?

It has been said that Jesus walked on water,

there’s the so-called Jesus Christ lizard,

so named because it can actually walk

on the surface of water.

A leaf can float on the surface of water.

Under some conditions,

a coin can float on the surface of water.

If you make coffee in the morning,

you can actually take a spoonful of that hot coffee

and pour a little bit on the surface of your coffee

and you’ll notice that it will bead up

and you’ll get little round spheres of water.

Those are little water molecules bound to one another

that spin on top of the surface before they sink under.

That has everything to do with the bonding between water

that’s dependent on temperature,

but also as with the difficulty for essentially everybody

to walk on water or for animals to walk on water,

the surface tension of water allows certain things

to float there or to stay at the surface,

but there’s a very thin layer of water molecules

at the surface of water that are more dense

than the water that resides at deeper depths

and that’s why most things, including us, sink in water.

We are more dense than water.

Now, I did mention earlier

that there are three forms of water.

Those are the ones that we all are familiar with,

the solid, liquid, and gas forms of water.

However, there are data mainly from Gerald Pollack’s

laboratory at the University of Washington

that have described the so-called fourth phase of water,

which is structured water.

And we’ll get into this a little bit later

because structured water has really been a prominent topic

in the, let’s call it the water health aficionados.

It’s a heavily debated topic

as to whether or not structured water

is somehow better for ourselves,

if it exists within our bodies.

We’ll get into that in full detail later,

but the whole notion of structured water

is that in the presence of certain solids or certain liquids

the conformation of water, that is the water molecules,

actually change somewhat.

This has been demonstrated.

Whether or not it has relevance

to the biological function of our body is a different issue,

but we know that there is this fourth phase of water

called structured water.

Structured water is a fairly complicated topic,

but we can make it very simple

for sake of today’s discussion.

I mentioned earlier that opposite poles attract,

that is positives and negatives attract,

and typically things that are negatively charged

when presented with another negative charge

either repel or don’t attract.

Things that are positively charged

in the presence of another positive charge

also tend to repel.

This is the basis of magnets,

either sticking to one another

or repelling from one another.

There’s also the idea that human beings

who are opposites attract,

but that’s a different episode

that we need to do in the future.

The point here is that structured water

is a unique condition in which the local environment

that these water molecules happen to be in

allows positive charges between different water molecules

to attract one another.

So again, whereas normally it’s positive and negatives

that attract, in the configuration

that we call structured water,

positives and positives attract

and form bonds that are stronger

than the typical bonds that would be formed

between water molecules.

And just as a kind of prelude to our discussion

about structured water,

as it may or may not relate to health later,

there are a number of people that believe

that within the body,

because of the presence of certain liquids and solids,

that the water within our cells,

and in particular within the interactions

with so-called organelles,

organelles are things like mitochondria,

the Golgi apparatus, they have fancy names.

These are the things within cells

that allow cells to do everything from make proteins

to traffic proteins out to the surface of cells,

things like neurotransmitters and receptors and so on.

A lot of people who are interested in structured water

as it relates to biological function

have hypothesized or like to debate rather,

whether or not in the body,

water is not just present in its liquid form

or gaseous form.

We know it’s not present in its solid form

unless you gulp down some ice cubes, for instance.

But there is a cohort of people out there,

including some fairly accomplished scientists

that believe that within the body,

the organelles of our cells act as a substrate

for water to exist in this fourth form,

this structured water form.

And that’s led to this whole niche industry

of people who are proponents

of consuming so-called structured water.

Again, we’ll get to that a little bit later.

So now you know what individual water molecules consist of

when you hear H2O,

hopefully you’ll get that visual image in your mind

of an individual water molecule being the peace symbol

and a bunch of those binding to one another

through these relatively weak bonds,

but strong enough that certain things can take place

like surface tension.

Keep in mind that surface tension of water

may relate to either standard bonds between water

or this fourth phase.

That’s heavily debated still.

But we certainly know that, for instance,

if you were to take a piece of wax paper or glass

and you were to pour some water on it,

you would notice that the water would bead up

or kind of aggregate at particular locations.

When you see that beading up

or the aggregation of water molecules

on a particular surface, you’re seeing two things.

This is actually kind of fun.

The next time you see it, you’ll know that the aggregation,

the beading up of water with itself,

so individual water molecules or many water molecules

kind of aggregating at one location

and making a bead of water,

that’s due to these bonds,

these covalent bonds occurring between water molecules.

But also you’ll notice that on a vertical pane of glass,

say in rain or on your windshield,

that the water will look almost like it’s sticking

to the glass.

And that’s because there are actually bonds

between the water molecules that have beaded up themselves

and the glass.

So water can not just bind to itself,

it can also bind to certain surfaces.

And the fact that perhaps if you drive your car,

if you were to tap the window,

or if a big enough bead of water formed on a window

that it would start to drip down,

and that’s because those bonds with the surface are strong,

but they’re not so strong that it stick at that location.

So it’s quite different than water

that is in its solid form, ice,

that can actually really adhere.

If you’ve ever had to scrape ice off a windshield,

so for those of you who live in cold regions,

you’re familiar with this,

have to scrape ice off a windshield,

you realize that the bonds between water in its solid form

and different surfaces is quite a bit stronger

than the bonds between different water molecules

with each other,

or the bonds between water and different surfaces

when they’re warmer.

So I do realize that for a lot of people listening,

that’s going to be a pretty deep dive

into the chemistry and physical properties of water.

But all you really need to know

is that these water molecules are incredibly versatile

and can bind to each other

and can bind to different surfaces

and can allow things to float or to sink

or even to move across surfaces of water

based on the three, perhaps four different states

that water can be in.

And that versatility that you observe in the natural world

on window panes and rain and clouds and hail and ice

and snow and scraping ice off your windshield

in the cold of winter and perspiration and so on,

all of that is fine and good,

but realize that almost all of those same sorts

of properties of water become extremely relevant

when thinking about how your body actually utilizes water.

And the key thing here is that temperature

and the so-called alkalinity or acidity,

that is the pH of water,

turn out to be very important determinants

of how water is used by the cells of your body.

In fact, as I’ll describe in a moment,

we have entire sets of biological mechanisms

solely devoted to trying to get water into our cells

in very specific ways, including at specific rates

and to use water in different ways

because as you’ve probably heard before,

we are mostly water.

What’s kind of interesting to me

and what I found researching this episode

is that the percentages of our cells and bodies

that are purported to be water is a pretty broad range.

Some people will say we’re 55% water.

Other people will say we’re 70% water.

Some people say we’re 95% water.

The exact percentage doesn’t matter so much

and really just boils down to whether or not

the person that’s stating that percentage

is talking about how much water is present

in our cells and body at a given moment

versus how much water was involved in the process

of creating the sorts of proteins

and other things of our body that are required

to have hair cells, skin cells, brain cells, et cetera.

So if you really want a number out there,

I can’t give you a single number.

If you want to be accurate, it’s going to have to be a range

and basically we are anywhere from 70% to 90% water

depending on how you define being water.

That is whether or not you’re talking about

water being present in cells in its liquid form

or maybe in this fourth structure water form

if you’re of the mind that that exists within us

and whether or not you’re talking about water

that was used to create a given protein

like a receptor or a neurotransmitter

or whether or not you’re talking about the water

just being water as H2O, okay?

So again, it’s very easy to go down that rabbit hole

and this is part of the reason

why there’s such a wide discrepancy of assertions

as to how much of us is water, but let’s be direct.

Most of our body is water and there isn’t a single

other molecule in the universe that we can look to

and say that it has as important a role

in our health and biology and frankly,

our presence of life on earth at all than water.

I’d like to take a quick break

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Okay, so now at a minimum, everyone out there

should understand that water has a particular structure.

So when you hear H2O, you can kind of imagine that structure

and that the water molecules can change their conformation.

That is, they can bind to other water molecules

and it turns out they can bind to other things

and actually change the conformation of other things.

A good example of that is something we’re all familiar with,

which is water’s ability to dissolve certain substances

like sugar or salt.

And that is because salt molecules or sugar molecules

are what we call hydrophilic, they like water.

And when we say they like water,

it just means that the chemical structure of salt, sodium

or the chemical structure of say sucrose, like table sugar,

can actually interact with the hydrogens and oxygens

of water and can change those salt molecules

or sugar molecules, turning them from solid into liquid,

essentially creating what are called solutes,

which is basically the dissolving of solids

into a liquid solutions.

In fact, water is one of the best solvents on the planet.

In fact, water is better at dissolving many solids

than is acid, right?

That’s how incredible water is.

And there are a number of reasons

related to the chemistry of water that can explain that.

But as we transition from talking about the physics

and chemistry of water to how water actually behaves

within our body and contributes to our health

or to disease, depending on the case,

it’s important to understand that molecules

such as sugar and salt can be hydrophilic

or as we know, oil and water don’t mix.

That’s because oil’s lipids are so-called hydrophobic.

What’s hydrophobic?

We’ll just think, ah, phobic.

Certain molecules such as lipids

don’t dissolve well in water.

And we all intuitively understand that.

If you take some olive oil, for instance,

and you put it into a little glass of water,

it’ll likely float or beat up or form a little spherical

or amoeba-like shapes within the water.

And that’s because oil lipids are hydrophobic.

So different substances out there

are either going to be more hydrophilic,

that is, they are going to have a greater propensity

to interact with water and bind with the different aspects

of the water molecules, or hydrophobic,

to have less of a propensity to interact with

and bind with water molecules.

And I’ve sort of been alluding to this numerous times

throughout this podcast already,

the temperature of water and the pH,

that is the alkalinity or acidity of water,

will have a strong impact on whether or not

a hydrophilic or hydrophobic substance

will have a greater or lesser tendency

to interact with water.

You all know this intuitively as well.

If you’ve ever tried to dissolve,

say, a big tablespoon of sugar in very cold water,

you’ll notice that the grains don’t dissolve as quickly

as when you take that big tablespoon of sugar

and put it into a warm or hot cup of water.

And that’s because the temperature of water

actually changes how well that sugar molecule

is able to change its conformation

and interact with the water molecules.

Likewise, if you want to get something

that’s really hydrophilic into an aqueous,

that is a water-containing solution,

the temperature is also going to strongly impact that.

Now, there are a near infinite number of examples

of how temperature and pH impact

the tendency of hydrophilic and hydrophobic substances

to dissolve in water or not.

We’re not going to go into all those details,

but as we migrate from our discussion

about the physics and chemistry of water

into how water behaves within our body,

which is what we’re going to do now,

and then as we continue into the third part

of our discussion, which is why and how

certain types of water that some of you are familiar with,

like different pH water, distilled water,

reverse osmosis water,

why those different types of water are thought to,

and in some cases do, in fact,

change the ways that our cells function

for better or for worse,

all of that will come together and make sense for you.

Okay, so all the cells of your body, every cell,

even your bones, that is the osteoblasts

and the other cells within your bones,

your bone marrow, your red blood cells,

your white blood cells, your neurons,

your nerve cells, your liver cells, your kidney cells,

all of them require water.

In order to get the proper amount of water into those cells,

there are basically two ways

that water can access those cells.

Now, if we zoom out for a second and ask ourselves,

how does water actually get into the body?

Most of us just think,

oh, well, we drink that water into our body.

Of course, that’s the main way.

We can also breathe water molecules

into our body through humid air.

When you hydrate your cells,

that is when you’re bringing water into your cells,

that water needs to move from your gut

and into the bloodstream

and eventually into the individual cells,

whatever cell type that may be.

And there are basically two ways

that water can access those cells.

The first way has been known about for a very long time,

and that is so-called diffusion.

Now, the outside of most cells

is made up of fatty stuff, lipid.

So for instance, neurons, nerve cells

have a lipid bilayer, it’s two layers of fat.

And you already know that fat, lipid, is very hydrophobic.

Now, that turns out to be not a problem,

but a solution for how water can get

across that lipid barrier.

Why?

It is the fact that water can change its conformation

and lipids can change their conformation just enough

so that the bonds between water

and the bonds between those hydrophobic lipids can interact,

allowing the water molecule

to basically pass through the lipid

because it can bond very weakly,

or in some cases, not at all,

but very weakly to those lipids,

and then be pushed through to the other side.

Really incredible if you think about it.

If there was too much of a hydrophobic relationship

between the lipid and the water,

the water would come up to the surface

of that fatty outside of our cells,

and then would be repelled away from it,

or would just stay there right at the surface.

And that would be no good

because we actually need that water

to diffuse across the cell membranes,

or actually it’s a double cell membrane,

as I mentioned before, two layers.

So water and lipids of cells can interact

with just enough affinity

that the water molecule can diffuse

across those cell membrane barriers.

But, and this is an important but,

the diffusion of water molecules

across those lipid barriers on the outsides of cells

is a fairly slow process

compared to the other way that water accesses cells.

And this other way that water accesses cells

is really something that was just discovered

about 10 years ago.

So this is a fairly recent discovery,

but it turns out to be a fundamental discovery,

which is the presence of what are called aquaporin channels.

Aquaporin channels are basically portals

through the membrane that allow water molecules

to move very quickly across cell membranes

at a rate of about 1,000,000 H2Os,

1,000,000 water molecules per second.

And the way that water molecules move across

the cell membrane through those aquaporin channels

is very interesting.

The inside of those channels,

and the way I think of these is they’re literally tubes

stuck through the membranes of cells.

The insides of those channels are very hydrophobic,

allowing those water molecules to just jut really quickly,

almost as if in your mind,

you can just imagine as if it was lubricated for the water,

although it’s not really lubricated.

The water molecules can move through in single file,

a million per second.

Now, why would you need two ways

for water to get across cell membranes?

One fairly slow through basic diffusion.

And again, diffusion, folks,

is the movement of things from a gradient

of higher concentration to lower concentration.

We just think about this as things tend to run downhill

from higher concentration to lower concentration.

They try and create equilibrium across space.

So, you know, if you had a bunch of marbles

on one side of a box,

just imagine that these were water molecules.

Because of the charges between those hydrogens and oxygens,

there’s a tendency for those marbles to spread out

and essentially take on a fairly even conformation.

That’s basically just diffusion across a space.

Water molecules will also move from higher concentration

to lower concentration across cell membranes.

And then you have these portals,

these tubes or these channels, as they’re called,

these aquaporin channels

where water molecules can move very quickly.

Now, the reason why biology seems to have created

these aquaporin channels,

and again, I wasn’t consulted at the design phase,

but the most logical explanation

is that we have many tissues within our body

that often need water very quickly

or need to release water very quickly.

Let’s think about a couple of these,

and then let’s look at what the actual distribution

of aquaporin channels is throughout the body.

What is an area of your body that on occasion

will need to move water very quickly out of it?

You can use your imagination here,

but I’ll just tell you that, for instance,

your tear glands or tear ducts

need to release tears very quickly.

So you need to take water that’s stored in your body,

if there’s an emotional experience,

or if you look at a very bright light, for instance,

or God forbid, if you get some sort of irritant in your eye,

you’re going to start to tear up.

And those tears are the release of fluid

from those tear ducts.

And so it’s going to be the very rapid release

of water from those tear ducts

through so-called aquaporin channels.

And in fact, aquaporin channels are heavily expressed.

There are many of them in the cells

of the so-called lacrimal glands that release tears.

In addition, we need to absorb water from the gut.

And the gut has a lining, endothelial lining,

and other cell linings, mucosal lining,

and water needs often to move very quickly

from our stomach into the rest of the body.

And one way that is accomplished

is through aquaporin channels

that are expressed all along your gut.

So the discovery of these aquaporin channels

is really highly significant

in terms of understanding the different ways

that water can interact with

and get into the cells of your body.

Now, there are aquaporin channels,

not just in the lacrimal glands that allow for tearing

or within the gut, but in many tissues within your body.

And they even have different distributions

within those tissues.

In fact, as one looks at the expression

of the different aquaporin channels,

because it turns out there are different forms of them,

across all the cells and tissues of the body,

there’s really no single tissue within the body

except perhaps the bones of your body,

and perhaps the ligaments to some extent

that don’t have these aquaporin channels.

Some of you out there

may have heard of the so-called fascia.

Fascia and sheath muscles

are unique kind of connective tissue

that gives some pliability and yet some rigidity

that allow for a lot of the physical abilities

of your musculoskeletal system.

It’s incredible tissue.

We’ll do an entire episode about fascia at some point.

Fascinating, fascinating tissue.

Fascia even contain aquaporin channels.

So the role of aquaporin channels in fascia

probably relates to our specific needs

to be able to use specific muscle groups

in particular ways at particular times.

In other words, if you’re sleeping or lying down or sitting,

you’re not using your musculoskeletal system

as much as if you’re running

or performing some repetitive behavior.

It turns out that the aquaporin channels

in certain tissues like the fascia can be used

when we transition from low mobility states

to high mobility states,

allowing more perfusion or access of water

into particular cells of the body when we need it.

So just fascinating, fascinating channels,

these aquaporin channels.

And again, only discovered fairly recently.

So we’re still learning new things

about our biology all the time.

Now, a very important feature of the aquaporin channel

is that the movement of water molecules

across the cell membrane through those aquaporin channels

is strongly dependent on the temperature of water

and the pH of water.

This becomes especially important in our description

and our deep dive into so-called alkaline water

or higher pH water a little bit later.

But I’ll just give you a little teaser for now

because I’m sure that a number of people

are wondering about this.

If you go into the store or even a convenience store,

you will see pH water.

Now, every water has a pH, right?

Lower numbers mean more acidic,

higher numbers mean more alkaline or more basic.

You’ll see pH water that is 7.4, you’ll see 7.8,

you’ll see 9.8, you’ll see a huge range of these things.

And there are many, many different claims

about how the pH of water is important

for regulating the pH of the body.

Here’s the real story.

The pH of your body, that is the pH of the cells

at different locations in your body

is strongly, strongly homeostatically regulated.

What do I mean by that?

It means it doesn’t change that much,

which means that you have very specific

biological mechanisms that ensure the pH is maintained,

for instance, in the skin cells of your skin,

in the retinal cells of your eye, in your brain cells.

Now, it is true that across the body,

different cells and tissues have fairly widely varying pH.

Now, it has been said that the pH of bodily tissues

is generally between 7.2 and 7.4.

However, if you were to look at the pH of your gut,

and keep in mind that your gut is not just your stomach,

your gut is the entire pathway

ranging from your throat all the way down

to where you excrete things out of your body.

That entire pathway has different pH levels

depending on where you are

along the gut and intestinal pathway.

And in fact, having much lower,

that is more acidic pH at certain locations

along your gut pathway is what allows those gut microbiota,

those little microorganisms of which you have trillions

that are important for regulating everything

from neurotransmitter production to hormone production

that allow them to flourish and do well.

That said, except under conditions of hemorrhage

or changes in blood volume that are of a dangerous level

that can lead to seizure or even death,

the pH of the rest of the cells of your body

and also those gut cells doesn’t change that much

on a moment to moment basis.

So if somebody tells you

that you should drink alkaline water or alkalized water

as it’s sometimes called,

in order to keep your body more alkaline and less acidic,

there is essentially no basis for that

at a macroscopic level or even at a local level.

Now, what that does not mean

is that the pH of the water that you drink is not important.

In fact, if the pH of the water that you drink is too low,

that is if the water that you consume is too acidic,

it will not move as quickly from your gut

into the other regions of your body

and therefore the other cells of your body

that require that water

will not be able to access it as readily.

You’ve probably experienced this

if you’ve consumed certain water

and it feels like it’s sloshing around in your stomach

or it feels like it’s just somehow staying there

or you feel its presence more, not just as volume,

but it’s almost as if you can feel the little waves of water

along the inside of your gut.

Now, sometimes that can relate to temperature,

but oftentimes that can relate to the pH of that water.

And it turns out it is true that water

that is more alkaline, that is pHs of 7.4 or higher

can move more readily across the aquaporin channel.

And in terms of absorption of water

from the endothelial lining

and the other cell type lining of your gut

into the rest of your body,

it is true that higher pH water,

provided that pH isn’t too high,

is going to be absorbed more quickly,

which partially explains why some people have an affinity

for this higher pH water.

Now, this is not to say that you need to consume

high pH water in order to hydrate your body properly.

I want to be very clear about that.

However, if you are interested

in what the value of elevated pH water is,

it largely has to do with this accelerated absorption.

And as we’ll talk about a little bit later,

there is also growing evidence

that it can adjust the function of certain cells

that are within your immune system

and thereby reduce certain inflammatory responses.

So I realize as I’m saying this,

some people out there are probably thinking,

oh no, this guy’s like a pH water proponent.

He’s saying we have to drink alkaline water

or buy very fancy water.

Now, I want to be clear, that is not what I’m saying.

And I’m also not saying that you need

to purchase very expensive water

in order to derive the maximum benefits

from the water that you drink.

It turns out there are a few things that you can do

by way of temperature and by way of filtering water

and a few other tricks that I’ll tell you a little bit later

that will allow you to increase the absorption rate

of water in the gut,

which turns out to be a very interesting

but also potentially important thing to do

for not just reducing inflammation,

but also making sure that you’re getting proper hydration

of different cell types in your body,

including rapid hydration of your brain cells,

which as we’ll also talk about in a few moments

can greatly enhance cognitive function.

Okay, so we’ve talked about how water can get into cells.

There are two ways, diffusion and movement

through these aquaporin channels.

We’ve earmarked the discussion that the temperature

and the pH of water, that is the confirmation of water.

And here, I really want to embed this in people’s minds

that when we talk about temperature of water

and pH of water,

we’re really talking about the arrangement of those H2Os,

those water molecules.

So keep that in mind.

We’ve covered how water can get into cells

through those two different ways,

diffusion and through the aquaporin channels.

What we haven’t talked about

is what happens to water once it’s in cells.

And this is very simple to explain.

Once water is inside of cells,

it’s going to be incorporated

into the different proteins and organelles.

Again, organelles are things like mitochondria,

the nucleus of the cells,

which contains the DNA and so forth,

in different ways, depending on which proteins are there

and how hydrophilic or hydrophobic those proteins are,

or in some case, aren’t.

That’s an entire landscape

of protein to water specific interactions,

none of which we need to go into in any specific detail now.

But the one thing that we do need to realize

and keep in mind as we go forward

is that many of the biological processes in our body

that involve the movement of molecules,

such as water and interactions with proteins

are going to involve the bonding or lack of bonding

between water molecules and proteins.

And anytime we’re talking about bonding

of one thing to the next at the level of chemistry

or biology for that matter,

because they’re really the same thing,

we’re talking about whether or not there are electrons

present or whether or not there are charges

that are opposite or the same and on and on.

If you’ve ever heard of so-called reactive oxygen species,

what are ROSs or reactive oxygen species,

or so-called free radicals or antioxidants,

all of that is really just describing

the presence or absence of charges

that are bound or unbound.

So for instance, if you hear about free radicals,

sounds pretty wild, right?

Free radicals, what are free radicals?

Free radicals can damage cells.

They don’t always damage cells,

but they can damage cells

because they are essentially free electrons.

They are a charge that’s sitting out there,

not bound to anything,

and therefore can interact with the molecular structure

of certain proteins and change those structures

by binding to them or interfering

with the normal binding processes of those proteins

to water or to other things.

And in that way, cause damage to those proteins

and potentially damage to cells.

Now, fortunately, our cells have ways to deal

with those free radicals,

and those are called antioxidants.

Antioxidants are molecules that can arrive in different forms.

Sometimes we think of antioxidants as vitamins,

but they are also present in other things as well,

that essentially bind up those free radicals

or repair the bonds between cells

so that the proteins are no longer undergoing these,

let’s just call them bad conformations

that damage the functioning of our cells.

So there are many different theories of aging.

There are many different theories of disease,

but there is not a single disease either of brain or body

that doesn’t in some way involve the generation

of what are called reactive oxygen species,

these free radicals and the damaging of cells

at the level of their individual organelles and so forth,

nor is there a single disease of brain or body

that has not been shown to benefit

from having some antioxidant interference

get in the way of that oxidative process.

So I realized today is pretty thick with nomenclature.

For those of you that haven’t already realized it,

what you’re learning here is organic chemistry.

So you can feel pretty good about the fact

that if you can understand the water molecule

and understand a little bit about what free electron is,

which is basically a charge that’s out there

that can potentially do damage,

and the interactions of things like reactive oxygen species

and the ability of stable bonds to buffer against

or repair certain damage to cells

as we’re describing it here,

well, then what you’re essentially thinking about

and what we’re talking about is organic chemistry.

Now, since this is a discussion about chemistry

as a service to try and understand

the biological effects of water,

keep in mind that water itself, believe it or not,

can act as an antioxidant

provided that it’s bonding to things in the proper way,

which requires that it get into cells

in the proper amounts and rates,

which requires that the temperature and pH of that water

be correct and provided that there’s enough water there

and that that water isn’t bound to other things.

It’s not containing solutes that are damaging

and potentially that it’s carrying some of the good things

such as sodium or that there’s potassium present.

Again, the so-called electrolytes

that allow cells to function well.

Okay, so that’s a bit of a trench of information

and I don’t want people to get overwhelmed or confused.

What I’m trying to do here is paint a picture

of the biology of water,

understanding that when you ingest water,

drinking it down or when you breathe water vapors

in the steam room or on a humid day,

that water is entering your system,

it’s accessing your cells through these two mechanisms,

diffusion across cell membranes

or movement through aquaporin channels,

and then once inside those cells,

it’s able to interact with and change the conformation

of different proteins and accelerate or slow down

different cellular reactions,

everything from normal metabolism to blood pressure

to damaged cells, depending on a number

of different features of that water,

as well as what the cells happen to be doing

at any given moment.

So with that in mind, I’d like to turn our attention

to how water, depending on its temperature, its pH,

how much we drink or how little we drink,

when we drink that water, et cetera,

how that can impact the health, disease,

and repair of different cells, tissues,

and organs of our body.

I’d like to just take a brief moment

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Let’s talk about how much water, or more generally speaking,

how much fluid each and all of us should drink each day,

and how much fluid to drink

depending on our specific activities and environment.

Now, this is perhaps the most commonly asked question

when the topic of water comes up.

How much water do I need to drink?

The other thing that comes up is a question,

which is, can’t we just follow our natural thirst?

That is, can’t we just pay attention to when we’re thirsty

and then drink fluids?

And then that leads to the other question,

which is, does the color of our urine provide any indication

as to whether or not we are under-hydrated, over-hydrated,

or hydrating correctly?

So let me answer each of these things one at a time.

And in the backdrop, I want to highlight the fact

that there are many, many, if not dozens,

hundreds of studies pointing to the fact

that when we are dehydrated,

our brain doesn’t function as well,

and our body doesn’t function as well.

So what I’m attempting to do in that statement

is throw a net around the enormous number of studies

that have shown that even a slight state of dehydration,

even 2% dehydration,

can lead to a significant and meaningful impact,

that is, a negative impact on our ability to, for instance,

carry out endurance-type behaviors.

So our ability to run on a treadmill

and stop at the point where we feel like we can’t continue

is going to be negatively impacted.

That is, we will be able to perform less work

for less period of time

when we are even slightly dehydrated.

Likewise, our strength is reduced

by even slight dehydration.

Likewise, our cognitive performance,

including memory, focus, creative thinking,

flexible thinking of different kinds,

are all significantly impaired

when we are in states of dehydration.

Now, that raises an additional question

that deserves attention,

which is how do we actually measure dehydration?

Now, you hear different things.

Like if you pinch the skin on the top of your hand

and it takes more than three seconds

to lay down again flat, then you’re dehydrated.

You hear that.

You hear, okay, if you are to press on your fingernail

and see a change in the color of the tissue

just below your fingernail, which indeed does happen,

and it does not go back to its original color

within one to three seconds, then you’re dehydrated.

You hear things like this.

If your ankles are swollen when you’re wearing socks,

you take off the socks

and you can see the imprint of the socks

on your lower limbs, that means you’re dehydrated.

You hear this kind of stuff,

and you should probably be wondering, is any of that true?

To some extent, it is true,

although it can vary quite a bit by how old you are,

whether or not the skin on the top of your hand

tends to be looser or not,

depending on whether or not you’re leaner or not.

So in other words,

those are not absolutely objective measures of dehydration.

Now, it is true that if normally

you can pinch the skin on the top of your hand

and it returns to its normal flattened position

within about one to two or three seconds,

and it does not do that within five or more seconds,

there’s a decent probability

that you’re a little bit dehydrated,

that you need to ingest some fluid,

or that if you press down on your nail

and you see the depression causes a transition

from kind of a pink color to a white color,

and then you release,

and it doesn’t go back to its original pinkish color

within a few seconds,

well, then there’s a chance that you’re dehydrated.

But again, these are not perfect measures

of dehydration.

You may be surprised to learn,

and I was surprised to learn

that most of the basis for these statements,

like even a 2% dehydration state

can lead to significant reductions

in cognitive or physical performance

are based on not direct measures of hydration,

but rather on measures of reductions in water intake,

which is a different thing, right?

It’s saying that ordinarily,

a person of a given body weight

needs X amount of fluid per day,

and when they get even just 2% less

than that amount of fluid,

then their cognitive and or physical performance is impaired

rather than focusing on dehydration of tissues, right?

Now, that might seem like a subtle distinction,

but it’s actually a meaningful distinction

when you think about it.

However, it’s a meaningful distinction

that we can leverage toward understanding

how much water or fluid we need to drink each day.

Now, there, we can really point to some solid numbers

that, believe it or not,

are fairly independent of body weight.

Now, I say independent of body weight,

I’m referring to the amount of fluid

that most healthy adults need at rest.

What do I mean by at rest?

I mean, when not exercising

and when not in extremely hot environments.

So I’m leaving aside you desert ultramarathoners

or people that are doing any kind of movement

or living in environments that are very, very hot.

Here, I’m mainly referring to people

that live most of their daily life in indoor environments.

Could be air conditioned or not air conditioned,

heated or not heated.

What we’re trying to arrive at here

are some numbers that can work across the board

because, of course, there are an infinite number

of different conditions

that each and all of you are existing in.

So I’m not going to attempt to give you a body weight

by activity, by environment, by humidity formula calculation.

In fact, no such calculation exists.

However, there are formulas

that can put you into very stable frameworks.

That is levels of water intake for periods of rest

when you’re not exercising

and for when you are exercising

that will ensure that you are hydrating

with the one exception being if you are exercising

or if you are living in very, very hot conditions

and you’re not heat adapted to those conditions.

So what are those numbers?

In other words, what is the answer to the question

of how much fluid do we need each day?

And here I’m referring to fluid.

I’m not distinguishing between water,

caffeinated beverages, soda, tea, and so on.

I’ll discuss that in a moment.

We can reasonably say that for every hour

that you are awake in the first 10 hours of your day,

this is important, in the first 10 hours of your day,

you should consume on average eight ounces of fluid.

Now, for those of you that are using the metric system,

not ounces, eight ounces of fluid

is approximately 236 milliliters of water.

And for those of you that exist in the metric system

and aren’t used to thinking about ounces and vice versa,

just think about a typical can of soda

in the United States is 12 ounces.

In Europe, sometimes the cans of soda

are a little bit smaller.

That’s a whole discussion unto itself,

but eight ounces of fluid, that is 236,

let’s just say 240 milliliters,

because we don’t need to be too precise here,

of fluid on average every hour

for the first 10 hours of your day,

which translates to an average of 80 ounces of fluid

for the first 10 hours of your day,

or 2,360 milliliters of water.

In other words, approximately two liters of water

plus a little bit more for the first 10 hours of your day.

Now, I want to be very clear that this does not mean

that you need to ingest eight ounces

or 236 milliliters of fluid on the hour,

every hour for the first 10 hours of your day.

I’m certainly not saying that.

And in fact, most people are going to find

that they’re going to ingest water in boluses.

That is, they’re going to have perhaps 16 ounces of water,

500 milliliters of water at one portion of the day,

and then maybe a couple hours of later

they’ll drink some more water or some more coffee or soda

or some other beverage at another portion of the day.

I do think, however, it’s important for most of us

to take a step back and ask ourselves

whether or not independent of any other activity

or environmental conditions,

whether or not we are in fact ingesting 80 ounces

or basically 2.4 liters of water

for that 10 hours of the day

that spans from the time we wake up

until 10 hours later.

Now, why am I setting this 10-hour framework?

The reason I’m setting this 10-hour framework

is that it turns out that your fluid requirements,

even just at rest, are vastly different

in the time from when you wake up

until about 10 hours later

as compared to the later evening and nighttime.

And here I’m referring to people

that are not doing night shifts.

But if you are requesting a number

of how much fluid to drink,

independent of our needs for fluid for exercise,

that’s going to be eight ounces of fluid

or 240 milliliters of fluid on average for every hour

from the time we wake up until 10 hours later.

That’s the simple formulation

that should basically ensure

that you’re getting sufficient baseline hydration

for the cells and tissues of your body.

Now, if you are engaging in exercise,

whether or not it’s endurance exercise

or whether or not it’s resistance training exercise,

you are going to need additional fluids

in order to maximize the effects of that exercise

and to avoid dehydration.

And there too, we have some excellent numbers

that we can look to,

excellent because they arrive from research.

And this is largely peeled from the episode

that I did with Dr. Andy Galpin,

professor of kinesiology at Cal State Fullerton.

We did a six-episode series all about exercise,

everything from strength training, hypertrophy, endurance,

nutrition, supplementation, recovery,

everything related to exercise.

You can find all of that at hubermanlab.com.

And one of the components of those episodes

that was discussed,

but that some of you may have not heard,

is that there is a simple formula

for how much fluid to ingest on average.

Keep in mind, this is on average when you’re exercising.

And I refer to this as the so-called Galpin equation.

The Galpin equation states

that you should take your body weight in pounds,

divide that by 30,

and that will give you the number of ounces of fluid

to ingest every 15 to 20 minutes on average

while exercising, okay?

Your body weight in pounds divided by 30

equals the number of ounces of fluid to consume

on average every 15 to 20 minutes.

When I say on average, what I mean is

it is not the case that you need to stop

every 15 or 20 minutes and consume that volume of fluid.

You could sip it from moment to moment.

You could wait half an hour or an hour

and then consume a larger bolus of fluid,

a larger amount.

Although it is recommended for performance sake

that you sip or consume beverages

fairly consistently throughout your training.

One’s ability to do that is going to depend

on a number of things like gastric emptying time,

whether or not the particular exercise you’re doing,

whether or not it’s running or jumping

is compatible with ingesting fluid on a regular basis

or whether or not you need to do it at different intervals

than every 15, 20 minutes.

Maybe it’s every five minutes.

Maybe it’s every half hour.

You have to adjust for you.

But if you were to take the hour of exercise

or the half hour of exercise or the three hours of exercise

and ask how much fluid to ingest,

it’s going to be that Galpin equation

of body weight in pounds divided by 30

equals the number of ounces for every 15 or 20 minutes.

And of course I can already hear screaming from the back,

what about for those of us who follow the metric system?

And there there’s a simple translation

of the Galpin equation,

which is that you need approximately

two milliliters of water per kilogram of body weight

every 15 to 20 minutes.

Again, the Galpin equation converted into the metric system

is going to be two milliliters of water

per kilogram of body weight

every 15 to 20 minutes on average.

I’m sure a number of you are asking

whether or not hydration prior to exercise

is also important.

It absolutely is.

And if you follow the numbers that I talked about before,

approximately eight ounces or 240 milliliters

of fluid intake per hour in the first 10 hours of waking,

that should establish a good baseline

of hydration heading into exercise,

which then prompts the next question I often get,

which is, is the amount of water that needs to be consumed

according to the Galpin equation during exercise

on top of or separate from,

that is, does it replace the amount of fluid

that one needs at a basic level,

that eight ounces or 240 milliliters?

And there, the answer sort of goes both ways.

I think if you’re going to exercise,

then obviously follow the Galpin equation in some way.

Again, you don’t need to be ultra specific about this.

These are ballpark figures that will ensure hydration.

So we’ve set them a little bit higher

perhaps than needed to ensure more hydration

rather than less.

But basically the short answer is

if you’re exercising for about an hour,

most people are exercising for an hour or two,

probably not more than that.

Most of my workouts are,

and certainly the resistance training workouts

last about an hour.

Well, then you can replace the eight ounces

or the 240 milliliters of water

that’s required at baseline with what you consume

according to the Galpin equation

during that bout of exercise.

A common question is if you are exercising

in a heated environment, indoor or outdoor,

or you are somebody who tends to sweat a lot.

And by the way, we can all get better at sweating

by sweating more.

Sweat is an adaptation.

So if you sit in the sauna more,

you’re going to get better at sweating.

If you exercise more,

especially if you wear more layers

or if you do it in hotter temperatures

or more humid temperatures,

you’re going to get better at sweating over time.

And sweating is an adaptation that helps cool your body.

If you are sweating a lot or you’re in heat,

how much fluid should you ingest?

In general, I think it’s safe to say

that you may want to increase the values

on the Galpin equation by about 50 to 100%.

So either increased by 50% or double those numbers

if you’re in a very hot environment

or sweating an awful lot.

If you are sitting in the sauna,

I highly recommend consuming at least eight ounces

and probably more like 16 ounces of fluid.

So that translates again to about 240 or about 480.

Let’s just round up 500 milliliters of fluid

for every 20 to 30 minutes that you are in a hot sauna.

And then of course people ask, well, how hot?

And it, okay, that starts getting really detailed

and we can’t distinguish between dry saunas and wet saunas.

And again, too many variables,

but I would double your fluid intake

for that hot environment exercise

or for that hot environment sauna sit.

Also, if you are feeling dehydrated, okay,

what does feeling dehydrated mean?

That actually has a definition

that we can get into a little bit later,

but what we’re really talking about here

is if you are feeling as if your throat is dry,

you are quote unquote parched or you’re very thirsty.

Well, then there’s absolutely no problem

with ingesting more fluids, 16 ounces of fluid

or 500 milliliters of fluid per hour

while you’re feeling parched.

My read of the literature is that thirst

is a reasonable guide for when we tend to be dehydrated.

However, it is the case that our thirst

doesn’t really keep up with our body’s level of dehydration.

And we know that based on some really nice studies

that have explored the amount of fluid intake

compared to the amount of urination,

compared to the amount of physical output,

compared to the environment that one happens to be in.

These are sort of older studies in the realm of physiology,

but here’s the basic rule of thumb

that’s going to work for most people.

If you are feeling parched, consume fluids.

Ideally, you consume fluids that don’t contain caffeine

or other diuretics, diuretics being substances

that cause the release,

the urination of fluid from the body.

And, or if you are consuming caffeine either prior to

or after bouts of exercise, or even just at work,

or you work in a air conditioned

or otherwise dry, cool, or hot environment

that you try and include some sodium.

And ideally sodium, potassium, magnesium,

the electrolytes in that beverage.

So it could be a little pinch of sea salt

with some lemon to adjust the taste a little bit.

It could be an electrolyte drink of element

or some other sort.

There are a lot of different types out there.

For most people drinking pure water.

And I realized that many people do just like the taste

of pure water.

Chances are you’re going to have enough electrolytes

unless you’re sweating quite a bit

or you’re exercising quite a lot.

And under conditions where you’re consuming

very few carbohydrates,

you’re going to excrete more fluid.

If you are ingesting caffeine,

whether or not it’s from tea or coffee,

I highly recommend increasing your non-caffeine fluid intake

about two to one for every volume of caffeine.

So in other words, if you have a six ounces

or eight ounces of coffee,

you’re going to want 12 to 16 ounces of fluid,

ideally fluid with electrolytes,

or a little pinch of salt

in order to offset that dehydration.

Hopefully those will provide good rules of thumb

for what people want to do

when they’re just moving about their day.

Again, underscored by the fact

that even slight levels of dehydration

can really impair our cognitive and physical performance

largely by creating fatigue,

but more often than not by creating brain fog.

You know, I get so many questions about brain fog.

Why do I have brain fog?

Why do I have brain fog?

There is a vast literature showing that quality hydration,

meaning hydration that matches the demands of humidity

and output as described in the equations

that we went over a little bit before

really can enhance clarity of focus and overall energy.

And we’ll talk about why that is,

but I’ll just allude to it a little bit here.

The reason why ingesting sufficient fluids

can enhance our ability to focus

and in fact can reduce brain fog

and can increase physical vigor and output

is not mysterious to us.

We know that there are two mechanisms

by which fluid intake triggers elevated levels of alertness.

And it all has to do with the so-called sympathetic arm

of the autonomic nervous system,

which is a real mouthful,

but basically the sympathetic arm

of the autonomic nervous system,

as many of you heard me talk about before,

is the aspect of your nervous system

that makes you more alert.

It has nothing to do with emotional sympathy.

It has to do with a bunch of neurons

in the middle of your spinal cord

called the sympathetic chain ganglia

and some other related neural networks in your body,

as well as regions of your brain,

like the locus coeruleus that release things

like epinephrine and norepinephrine and make you more alert.

And in a kind of magnificent arrangement,

or I think magnificent arrangement,

when we have fluid in our gut

and when our cells are well hydrated,

and believe it or not,

when our bladder contains fluid within it,

there is an elevation in activity

of the sympathetic nervous system by way of two pathways.

One is mechanical.

In fact, we have so-called stretch receptors

in our bladder and in our gut.

These stretch receptors have fancy names

like TRP, trip channels, as they’re called,

or piezo, which are these stretch sensing channels.

This is the beautiful work of many laboratories,

but in particular, David Julius and Ardem Petapuchin.

David Julius is at UC San Francisco.

Ardem is at the Scripps Institute.

They’ve discovered a bunch of channels in cells

that sends things from cold

to different mechanical pressure,

including expansion of tissues, so-called mechanosensation.

And basically what it all boils down to

is that when our bladder has some fluid in it,

when our stomach has some fluid in it,

and when our cells are sufficiently hydrated,

they send information about the mechanical presence

of that distention.

And here I’m not talking about being overly full

or full chock-a-block full of fluid

or your bladder feeling really, really full.

We’ll talk about that in a moment.

But when we are sufficiently hydrated,

there’s a mechanical signature of that,

which is the expansion of our tissues

because it has more fluid in it.

And there are chemical signals as well,

which is the movement of water

across those aquaporin channels is actually understood.

And it’s a biological level by our cells

and sends information to the areas of the brain

that are associated with so-called sympathetic arousal

and makes us more alert.

This is actually what wakes us up

in the middle of the night.

If we have consumed too much fluid prior to sleep

and we need to urinate, we wake up.

This is a mechanism that is not adequately developed

in babies and young children.

This is why babies, young children often will wet their bed.

And believe it or not, in both humans and in dogs,

our ability to control urination voluntarily

is something that we actually learn.

Babies just pee in their diaper.

Dogs just pee on the floor until they’re housebroken

or until a child learns to hold on to their urine

until they go to the bathroom,

in a bathroom or particularly appropriate location,

outdoors or otherwise.

The point is that hydration of the body

is signaled to the brain.

When we have enough fluid in the tissues of our body,

when we’ve consumed enough fluid,

even if it hasn’t already arrived to the cells

and tissues of our body,

that is signaled to the brain in the form of alertness.

And that alertness is what translates

to the enhanced cognitive abilities that we have

when we are well hydrated.

It’s also what translates to our enhanced physical abilities

when we are challenged with physical tasks.

So when you look out on the landscape of all these studies

that have shown impairments in physical

or cognitive performance

under conditions of even slight dehydration,

that all makes sense because our cells need fluid

and we need water,

but it also prompts the question of,

well, does being well hydrated

actually make our brain and body function better

in the context of physical and cognitive performance?

And indeed the answer is yes.

Now, earlier we were talking about these equations

that you can apply.

And again, I really want to emphasize

that these equations were not meant to be followed

down to the decimal point.

They were really meant and are meant as crude

but sufficient guides for you to make sure

that you’re getting enough hydration

depending on your levels of activity and at rest.

If you recall, when we talked about those equations,

I said you need about eight ounces

or 240 milliliters of fluid per hour

for the first 10 hours of your day after waking.

Now, why did I say for the first 10 hours?

Well, it turns out that the filtration of fluids

from your body, which is accomplished of course

by your kidneys and by way of your bladder

and the excretion of fluid out urethra,

so-called urination,

is strongly, strongly circadian dependent,

meaning the cells of your kidney

and the cells even of your gut.

In fact, all the cells of your body,

but especially the cells of your kidney

which filter the fluid that comes into your body

and that makes certain hormones like vasopressin,

which is antidiuretic hormone,

all of that functioning of the kidney

is under strong regulation

by so-called circadian clock genes.

Circadian clock genes are genes

that are expressed in every cell,

but that in certain cells of the body

very strongly impact whether or not that organ,

in this case the kidney,

is going to be activated, meaning functioning,

at a very high level or at a reduced level.

And we can make all of this very simple

by simply stating what’s contained

in this beautiful review that I’ll provide a link to

if you want to learn more

called Circadian Rhythms in the Kidney.

And basically what is known

is that for the first 10 hours after waking,

your kidney is filtering fluid within your body

at a very rapid rate.

There are a number of different cell types that do that,

but they are basically taking that fluid,

pulling out any contaminants,

using hormones such as antidiuretic hormone,

vasopressin to adjust whether or not

you’re going to hold on to fluid

or release more fluid from your body in the form of urine,

depending on the salt concentration,

depending on how much fluid you need,

your work output, the conditions you’re in, all of that.

However, at about 10 hours after waking,

your kidney really starts to reduce

its overall level of functioning.

Now, that doesn’t mean that your kidney

cannot filter fluid 11 or 12 or 16 hours after waking,

but it becomes far less efficient at doing so.

And thank goodness it does

because you do not want your kidney filtering fluid

at the same rate at midnight,

assuming you wake up at say seven or eight or 9 a.m.,

that it was filtering fluid at 10 a.m.

In fact, we can say that if you want to reduce

your nighttime waking in order to urinate,

which is a common, common question and concern

that many people have,

how can I avoid waking up in the middle of the night

to urinate, and there I say,

it’s perfectly normal to wake up once,

maybe twice each night to urinate.

But if you want to reduce the number of times

that you wake up in order to urinate across the night,

maybe even make that number zero times,

you will greatly benefit by doing three things.

First of all, make sure that you’re hydrating sufficiently

during the daytime per the equations

that we talked about earlier.

That will ensure that you are not excessively thirsty

in the evening and therefore consuming a lot more fluid.

Second, and related to that first point,

is that you do want to reduce your fluid intake at night,

provided you hydrated sufficiently throughout the day.

And believe it or not,

the rate at which fluid moves from your gut

and into the cells and tissues of your body,

and then from your bladder into urine,

is determined not just by the volume of fluid you ingest,

but also the rate at which you ingest that fluid.

And you might be thinking, that’s crazy.

That makes no sense at all, right?

If I drink a ton of fluid slowly,

doesn’t it still mean that I’m going to urinate a ton?

Yes and no.

It also stands to reason that you might ask,

if I ingest very little fluid, but I do it very fast,

is it going to be the case

that I’m going to urinate it out very quickly?

Well, yes and no.

The point is that the fluid filtration systems of your body

that range from the gut to the bladder,

and include the kidney of course,

depend not just on the volume,

but on the rate of fluid that you ingest.

Because of those mechanosensors

that we talked about earlier,

if you gulp down a bunch of fluids,

you are going to excrete those fluids more quickly

than if you sip them slowly.

Excuse me, sip them slowly.

So here’s what I recommend.

Throughout the day when you’re trying

to get your adequate yield of water or other beverages,

feel free to gulp that fluid or sip it.

I’m a gulper, not a sipper,

but many of you are going to be sippers, not gulpers.

Consume fluid at the rate that feels right to you,

but feel comfortable gulping that fluid.

However, in the evening,

if you are somebody who has challenges

with waking up excessively in the middle of the night,

reduce your fluid intake,

provided you’ve hydrated properly throughout the day.

And I suggest consuming no more than five,

maybe eight ounces of fluid

between the time of 10 hours after waking

and when you go to sleep.

Again, if you’re very thirsty or you under hydrate

or it’s very hot, feel free to ingest more fluid, please.

But most people will find

that if they reduce their fluid intake

to about five ounces or less of fluid

in that later part of the day,

after 10 hours of having woken up and before sleep,

and they sip those beverages as opposed to gulping them,

that they will have fewer bouts

of waking up in the middle of the night

to go to the restroom and ideally zero.

Let’s talk about tap water.

And here I have to take a deep breath,

not a deep gulp, but a deep breath,

because in researching tap water

and what’s contained in tap water in different regions,

not just in the US, but around the world,

I confess the picture is a pretty scary one.

I want to be clear, I’m not somebody

who naturally orients towards fear or conspiracy theories.

However, in researching tap water for this episode,

by way of looking at the peer-reviewed research,

meta-analyses, reviews, specific research articles

where specific hypotheses were tested,

and in talking with experts in toxicology and so on,

it’s a pretty grim picture, frankly,

when one looks at what’s contained in most tap water

and whether or not the compounds

that are contained in tap water

are present in sufficient concentrations

to negatively impact our health.

And the bad news is that much, if not all tap water,

believe it or not, much, if not all tap water

contains things that are bad for the biology of our cells.

There is a silver lining, however,

and the silver lining is that very simple steps

that are very inexpensive can be used

to adjust that tap water to make it not just safe to drink,

but that makes it perfectly fine to drink.

So that’s the good news, and we’ll get to that in a moment.

If you are somebody who is interested

in whether or not tap water contains things

like endocrine disruptors, hormone disruptors

that can negatively impact reproductive health

in males or females or both,

there’s a wonderful review,

wonderful because it’s so thorough,

although the news isn’t great,

it’s very thorough, which is great,

which is entitled

Endocrine Disruptors in Water

and Their Effects on the Reproductive System.

This is a review from 2020 that analyzes water

from a bunch of different sources within the world

and essentially focuses on a few key components.

First of all, it focuses on the concentration of minerals,

that is magnesium and calcium within water.

Many people don’t realize this, but so-called hard water,

sounds terrible, right?

But hard water is water that contains magnesium and calcium,

which turns out to be a good thing.

Some water contains more magnesium and calcium,

other water contains less.

They looked at the presence of magnesium and calcium

because that is going to impact the pH of water.

In general, the higher concentrations of magnesium

and calcium in water, the higher the pH,

that is the more alkaline that water is

and the lower levels of magnesium and calcium,

the more acidic or lower pH that water tends to be.

The other thing that this review addresses

is the concentration of so-called DBPs,

dog, bulldog, porcupines, DBPs,

which are disinfection byproducts contained in water.

So obviously local governments, the government,

wants your drinking water to be clean.

They don’t want contaminants in it.

They don’t want sewage in that water.

They don’t want chemical contaminants

that are going to make people immediately sick.

So they treat water, water treatment plants,

treat water with disinfection products

and those disinfection products

create things called disinfection byproducts.

And the presence of those DBPs

or disinfectant byproducts can strongly impact

the pH of water by way of changing the concentrations

of magnesium and calcium.

Put differently, I do believe that governments

are trying to provide people with clean water,

but in doing so, oftentimes we’ll introduce things

to that water that are not good for us.

Now it’s very clear that DBPs can cause endocrine disruption

in ways that are not good for reproductive health.

I did a very long, in fact, four and a half hour episode

on fertility and vitality.

That was male and female fertility, by the way,

and vitality that again, you can find it hubermanlab.com

that talks about all the biological processes

involved in the generation of healthy eggs and sperm

and creating a healthy embryos,

implantation embryos and so forth.

It’s very clear that DBPs have been shown

to disrupt ovarian function,

spermatogenesis and fertility outcomes.

Even at concentrations of DBPs

that are present in drinking water

that comes from the tap.

Now, does that mean that you shouldn’t drink tap water?

Well, the answer to that is a, it depends.

What does it depend on?

Well, it depends on several things.

First of all, I highly recommend that everybody go online

and put in your zip code and ask for a water analysis

of water that comes out of the tap in that zip code.

This is something that is readily available online,

at least to my knowledge, and unfortunately,

there’s no specific one site that I can send everyone to

to get an in-depth analysis of the drinking water

that comes out of your tap.

However, I highly recommend that you go online

and put in your zip code or municipal area code

and figure out whether or not your water contains

X amount of DBPs or Y amount of DBPs.

Now, of course, you’re going to get a bunch of values back

and unless you’re a toxicologist,

you’re probably not going to know what those values mean.

But what you’re really looking for

is whether or not there are high, low,

or moderate levels of fluoride in that drinking water.

Why do I say that?

Well, there are studies that show that the concentration

of fluoride in drinking water is of particular concern

for the thyroid hormone system of the body.

Now, thyroid hormone has a lot of different roles

in brain and body, and thyroid hormone is very important

for everything from metabolism to levels of energy

when thyroid levels are disrupted

or if the thyroid receptors are disrupted,

it can lead to depression.

When thyroid hormones are optimized,

it can lead to optimal mood if there is such a thing.

But in other words, it helps keep your mood elevated.

It relates to everything from sleep to reproduction.

Thyroid hormone is involved in many, many things,

including bone health and tissue health generally.

So essentially every biological process in your body

is impacted by thyroid hormone.

And there’s a study that I’d like to highlight,

which was published in 2018.

And the title of the study is

Impact of Drinking Water Fluoride

on Human Thyroid Hormones.

This was a case control study,

so this is not an extensive analysis of many individuals.

However, what it shows is that fluoride

negatively impacts thyroid stimulating hormone

and so-called T3 levels.

So you have thyroid hormone T3 and T4,

even in the standard concentrations that are present of,

and here’s an important number, 0.5 milligrams per liter.

Okay, so if you can get ahold

of the fluoride concentrations in your tap water

and find out whether or not the concentrations

are at, below, or exceed 0.5 milligrams per liter,

what you will find is that even just 0.5 milligrams

per liter of water can disrupt thyroid function.

And this is going to be a particular concern

for people to have familial,

so genetically related thyroid issues,

or that are concerned with keeping

your thyroid hormone levels healthy,

which I think is everybody.

So I am telling you that you should try

and get ahold of some data about the water

that comes out of your tap,

if you intend on drinking tap water,

and probably even if you don’t,

just know what’s in your drinking water.

Your local government should provide that information

and or it should be readily available online.

And in particular, I think it’s worthwhile

to address how much fluoride is present

in your drinking water.

Again, I don’t want to create a lot of scare.

I’m not trying to trigger fear here.

I do think, however, by way of reading this review,

by way of reading the paper

that I just referred to a moment ago,

again, links to these are going to be provided

in the show note captions,

that there is extensive evidence

that elevated levels of fluoride in drinking water

are simply not good for us.

Now that could open a whole discussion

of why fluoride is in our drinking water

in the first place at all.

But leaving that aside,

it seems to me that most everybody should know

how much fluoride is in their drinking water.

And ideally, everybody, yes, everybody

is filtering their drinking water.

Now, that raises the question

of how best to filter drinking water.

And that brings an answer of,

it depends on a couple of things.

First of all, how healthy or unhealthy

do you know yourself to be?

So if you’re somebody who has no health issues,

you have plenty of vigor, you’re sleeping well at night,

you have no autoimmune disease,

you’re not aware of any health concern, minor or major,

well then perhaps you’re somebody

that doesn’t want to filter your water.

I would argue that why wouldn’t you employ

some very low or even zero cost approach

to filtering your water?

There are going to be other individuals

who are suffering particular ailments of brain or body,

or both, that absolutely should be filtering

their drinking water if they’re getting

their drinking water from their tap

because it is pretty well established now

that tap water contains a lot

of these disinfectant byproducts,

as well as in most cases,

exceeding the threshold of fluoride

that we know to be healthy for us.

How should you filter your tap water?

Well, you have everything ranging

from the so-called Brita type filters,

so these are going to be carbon type filters

or other filters that you essentially put

over a container or a compartment

where you can pour the water over it

and it goes into the compartment below.

Will those work?

Are they sufficient to filter out

the disinfectant byproducts?

The general answer is yes,

provided you change the filters often enough.

However, it is not thought, unfortunately,

not thought that they filter out sufficient fluoride.

So what I highly recommend is,

depending on your budget,

that you go online and you search

for at-home water filters that can filter out fluoride.

There are a number of straightforward

and inexpensive tools to do that.

And here, I don’t have any relationship

to any of the water filters

or things that I’m going to mention now.

I want to be very clear about that.

There’s no brand code or affiliation here.

I’m simply trying to direct you to resources

that will allow you to filter your tap water

for it to be more safe for you to consume

in a way that meets your budget

with the understanding that people have

very different disposable incomes.

So the range of costs here is going to be pretty tremendous.

I just want to get that out of the way first.

You know, there are water filters

that you can use repeatedly.

So these are what I’ll refer to as pitcher filters

that are less than $100.

Now, keep in mind that that’s a one-time purchase

except for the replacement of the filters,

which fortunately doesn’t have to be done too often.

So there are different filters.

I’ll provide a link to one that I found

that is at least by my read of the lowest possible cost.

So this is the so-called clearly filtered water pitcher

with affinity filtration.

So this is a filter that can adequately remove fluoride,

lead, BPAs, glyphosates, hormones,

and some of the other harmful things

that are contained in most tap water.

Again, I do realize that for some people,

even an 80 US dollar cost is going to be prohibitive,

but do realize that what you’re doing here

is you’re purchasing a unit

that can be used repeatedly over and over.

The reason why it’s lower cost

than some of the different filtration approaches

that I’ll talk about in a moment

are that you can’t really put all the drinking water

that you would use, say, for an entire week

or for an entire month in one pitcher.

You’re going to have to repeatedly pour water

into the pitcher in order to filter it.

Now, as I mentioned before,

the range on water filter costs

for filters that can adequately remove fluoride

and all the other things that you want

out of your tap water is immense.

In fact, you can find whole house water filters

that are $2,000 or more.

Again, these are going to be filters

that are going to be in your garage

or in a laundry room that are going to basically pull

from the piping system of your house

and deliver purified water.

Technically, it’s not purified,

but that’s removing these contaminants and fluoride

from all the sinks in your house.

So you could effectively drink

from any or all things in your house.

That’s what explains the higher cost.

I think most people are probably not going

to have the disposable income

or have the opportunity to include

one of these whole house filters.

Although if you do have the means

and it’s important to you, you could do that.

And then there are going to be

what I would call intermediate systems.

So systems that cost somewhere between 200 and $500.

Probably one of the more common ones

or popular ones is a so-called Berkey filter system.

These are filter systems that again,

remove the things that you want removed from your tap water,

and they can do it at higher volumes.

And they’re typically countertop units.

They don’t require any plugin typically,

or they only require brief plugin and electricity.

And they’re going to filter out many, many liters

or tens of liters of water

so that you can always have access

to that clean filtered water at any time of day or night

without having to pour over into the pitcher.

So I mentioned these different options,

because again, I realized that people

have different levels of disposable income.

As far as I know, there’s no tablet or simple mechanism

that can be purchased as a transportable pill

that you can just simply throw in water

and remove the contaminants.

If anyone is aware of one that can adequately remove fluoride

and other contaminants,

please put in the comment section on YouTube.

That’d be the best place

so that I and everyone else can see it.

But hopefully the mention

of the different filtration systems that I mentioned

will give you some choices that I would hope would fall

within the range that one could potentially afford.

An important note about filtration.

Just as in our body,

there are mechanisms to signal mechanical changes

and chemical changes that occur in our gut, in our brain,

et cetera, elsewhere.

And in general, both mechanical and chemical changes

are signaled across the body to invoke different changes,

whether or not those are a response of the immune system

or to make us more alert or more asleep, et cetera.

So too, filtration capitalizes

on mechanical and chemical filtration.

What I mean by that is when you run a fluid,

water or any other fluid through a filter,

those filters are doing two things.

They are physically constraining

which molecules can go through by creating portals, pores

that allow certain size molecules to go through

and not others.

And almost always they contain certain chemicals themselves.

Those filters have been treated with certain chemicals

that neutralize certain other chemicals.

So you may be wondering how, when you filter water,

magnesium and calcium could get through, but fluoride doesn’t

and that’s because these filters

have been very cleverly designed

in order to neutralize fluoride

or to prevent large molecules such as sediment and dirt,

which is kind of easy to imagine being filtered,

but also to allow certain small molecules like calcium,

which is small-ish or magnesium, which is small-ish

to still pass through into our drinking water.

And this is wonderful because what it means is that

by filtering our water using any of the methods

that we talked about before,

you’re still going to get whatever magnesium and calcium

is present in that water

while still adequately removing the fluoride

and other disinfectant byproducts.

Now, what if you can’t afford any of those options?

Okay, well, here you have an interesting zero cost option.

It’s not as good as the other ones of filtering that water,

but it is an option.

And I do think it’s important to give options to people

who don’t have any disposable income

for the purpose of filtering their water,

which is to draw a gallon or five gallons

or maybe even more tap water out of the tap

and put it into some container, some vessel.

So it could be one gallon, five gallon, 10 gallon container.

And then to let that tap water sit for some period of time

to allow some of the sediment to drop to the bottom.

Now you might say, well, there’s no sediment.

There’s nothing contained in that tap water

and isn’t fluoride diluted in the water?

And indeed the answer to that is yes.

However, there is some evidence that letting tap water

sit out at room temperature and outside the pipes

that deliver that water can help remove some,

if not all of the contaminants in that water.

If however, you are filtering the water

using any of the methods that I talked about

a few moments ago, you do not need to do this, okay?

I realize there’s a whole world out there

of people who insist on putting their water in the sun

or only keeping it in certain containers

and putting it out for a few days before they ingest it.

That to me seems a bit extreme.

If you want to do that, be my guest,

but I don’t think most people need to do that.

However, I do believe that for people

who have zero disposable income to devote

to paying for any kind of filtration system

for their tap water, that taking that tap water

and putting into some container at room temperature

and keeping it at room temperature

for a half day or a day or more,

and then pouring off the top two thirds of that water

into another container and consuming the water

from that second container is going to remove some,

not all of the contaminants

that one would need to be concerned about.

And here I should mention something

that I neglected to mention a few moments ago.

If you’re going to do this zero cost option

and let the water sit out for a bit,

you would want that water to sit uncapped.

Sorry, I should have mentioned that before, uncapped.

Of course, trying to keep things

from falling into that water.

In fact, you could even put a little bit of cloth above it.

So you don’t want things falling into that water,

but you want certain things to be able to evaporate off.

And you also want some of the sediment to drop down.

And the reason why this process of letting water sit out

would work at all is because many of the contaminants

contained within water are not present

because of the source of that water

or even the treatment of that water,

but rather because of the pipes that that water arrives

to your glass or the pot that you have from.

Okay, and here again,

there’s an infinite number of variables.

So some people are living in buildings

for which the pipes are very, very old,

but very, very clean, believe it or not.

Some people are living in newer buildings and structures

that have new pipes,

but for which the seals between those pipes

contain things that are not good for you to consume.

So by letting water sit out for a while,

you’re able to remove some of the contaminants

present within the pipes of your home and the building,

and even the pipes that lead to your home or apartment.

Now, some people get really obsessed

with this whole tap water thing

and really want to find out all the details about the pipes

and what sorts of hard metals and how much magnesium

and how much calcium are present in their water.

There are ways that you can test your drinking water

for those sorts of things.

Most people I realize, including myself,

are simply not going to do that.

If you want to know what I do,

I tend to drink water that is filtered

through one of these lower cost filters,

or if I’m going to be consuming a lot of fluid,

I will drink certain kinds of fluid that later I’ll tell you

I’ve been doing an experiment for sake of this episode,

looking at so-called molecular hydrogen water,

which sounds very fancy and esoteric

and almost a little wacky,

but it turns out it has largely to do

with the amount of magnesium and calcium

and the pH of that water.

So if you are somebody who has a very low budget

or simply just wants to spend a very small amount of money

and try and still drink tap water,

there is absolutely a way to do that safely,

but it does require a few of these steps.

So on the topic of magnesium and calcium,

this relates, as I mentioned earlier,

to the quote-unquote hardness of water.

So what of the hardness of water?

You know, is it better to have more magnesium and calcium

in your water or less?

Some people don’t like the taste of hard water.

They prefer the taste of water

that has less magnesium and calcium.

However, there I would encourage you to take a step back

and consider some of the literature.

In fact, I’ll mention a paper in particular

now published in 2019,

which describes the quote,

“‘Regulations for Calcium, Magnesium,

or Hardness in Drinking Water’

in the European Union Member States.”

Turns out in Europe, they do very detailed water analysis,

and that’s present in a number

of really high-quality scientific publications.

This was a paper published

in Regulatory Toxicology and Pharmacology,

and they cite a number of different references

in the introduction that, for instance,

and here I’m quoting,

“‘Statistically significant inverse association

between magnesium and cardiovascular mortality.’”

Now again, that’s an association.

This is not causal,

but higher magnesium in water,

lower cardiovascular mortality.

They go on to say,

“‘The highest exposure category,’

which are people consuming drinking water

with magnesium contents of 8.3 to 19.4 milligrams per liter.'”

Again, when you get your water analysis,

you can compare against some of these values.

“‘Was significantly associated with decreased likelihood

of cardiovascular mortality by 25%

compared with people consuming magnesium content

of 2.5 to 8.2 milligrams per liter.’”

Okay, so what this basically shows,

and by the way, the reference to that,

I’ll also provide a link to in the show note caption.

What this basically states

is that higher magnesium-containing water,

and it turns out higher magnesium

and calcium-containing water,

so-called harder water,

may not taste as good to you,

but turns out to be better for you.

Now, whether or not it can prevent you

from getting cardiovascular disease, I don’t know.

In fact, I would probably just state no,

it probably won’t prevent you from cardiovascular disease.

You still need to do all the other things

that are important for avoiding cardiovascular disease

and cerebrovascular disease.

For that and what to do

in order to avoid cardiovascular disease,

I strongly encourage you to listen to the episode

with Dr. Peter Atiyah that’s coming out in a few weeks

that gets deep into that topic

and the actionable items

for avoiding cardiovascular disease.

But basically, as this study quotes,

there is a growing consensus among epidemiologists

and epidemiological evidence,

along with clinical and nutritional evidence,

that’s strong enough to suggest

that new guidance should be issued

in terms of how these different sources of tap water

should enhance, not deplete,

the amount of magnesium and calcium in that water.

Now, this ought to raise a very important question

in all of your minds, which is,

why is it that magnesium and calcium concentrations

are relevant to cardiovascular disease?

Is it something about what magnesium does in cells

or what calcium does in cells?

Are we all magnesium and calcium deficient?

Well, it turns out that’s not the case.

The major effect by which magnesium and calcium in water

are likely to impact things like blood pressure,

cardiovascular disease,

and other aspects of cellular function

turn out to be somewhat cryptic,

but we can make that cryptic aspect very clear

by saying that when we have more magnesium in particular,

but also calcium present in our water, so-called hard water,

you increase the amount of hydrogen in that water.

It becomes what we call hydrogen-rich,

and the pH of that water is increased.

Now, again, this does not mean

that we are trying to change the pH of the cells of our body

in any kind of meaningful way.

In fact, we don’t want to do that.

We want the pH of the cells of our body

to stay in particular ranges, as I mentioned earlier,

but having more magnesium and more calcium in our water,

that is increasing the hardness of our water,

changes the pH of that water,

and it turns out that the elevated pH of water,

that is pH of water that tends to be

somewhere between high sevens,

so we could say 7.9 up to even nine or 9.2,

is going to be more readily absorbed

and is going to more favorably impact

the function of our cells than lower pH water.

Again, I want to restate this

because I’m a little bit concerned

that maybe a clip of this is going to be taken

and sent elsewhere,

and someone will get the impression that I’m saying

that we actually want to drink high pH water,

that we all need to buy expensive high pH water.

It turns out that’s not the case.

If you are consuming tap water from a location

where levels of magnesium are sufficiently high

in that tap water, again,

where the level of magnesium is 8.3 to 19.4 milligrams

per liter of water,

that is if the water coming out of your tap is hard enough,

well then chances are you don’t need

to enhance the pH of that water

or change its magnesium concentration.

If however, the water that you’re drinking from the tap,

filtered or not, I would hope filtered,

contains less than 8.3 milligrams per liter of magnesium,

well then chances are the pH of that water

is going to be low enough

that it’s not going to be lending itself

to some of the favorable health components

that higher pH water can.

Notice I did not say that lower pH,

aka more acidic water is bad for you.

I didn’t say that.

I said that higher pH water can be good for you.

So let’s talk about how and why higher pH water

can be good for you,

and some of the best,

and in fact, very inexpensive sources

of higher pH magnesium enhanced,

or simply tap water that contains sufficient magnesium

can be used and accessed.

Many of you are probably wondering whether or not

you can simply boil your tap water

and thereby decontaminate the tap water.

There I want to caution you.

It turns out that some of the contaminants present in water

are actually made worse by heating water.

And again, I don’t want to open up,

you know, a whole catalog of different fears.

I, like all of you, I presume, use water to cook,

pasta, rice, because I’m an omnivore.

I do consume those things.

I confess if I make your beurre maté,

or any kind of tea or coffee,

I tend to use a higher quality water source than tap water,

even if that tap water is filtered,

because I like the taste far more

if I use a really good source of water.

And again, because I’m not consuming those beverages

in enormous volumes,

that becomes a relatively inexpensive endeavor.

But I would caution people against using boiling

or heating of water as the only method

to decontaminate their tap water,

and instead to also rely on some of the filtration systems

that I talked about before.

And as long as we’re talking about the temperature of water,

there is sort of an ongoing debate online.

It’s not a huge debate,

but a number of people engaged in this debate

as to whether or not drinking really cold water

or room temperature water is better for you

or worse for you.

This is a tough one to resolve.

It turns out that if water is very, very cold,

that is, if you drink it and you can feel that cold water

making its way down to your gut,

and you can actually feel it as cold within your gut,

and that’s sort of a back of the envelope,

or I should say direct within the gut measure

of cold versus body temperature water,

that it is going to be slower to absorb.

That is, you’re going to feel it sloshing around

in your stomach for a bit longer

than if you were to consume water that is slightly warmer.

Now, that is not to say that you should ingest warm water

or room temperature water.

However, many people find that when they drink

very cold water or ice water,

that indeed it can alter the kind of sensation

of the lining of their stomach in ways that,

at least to them, feel like it’s altering their digestion.

And that makes sense.

The cells that line the gut are very temperature sensitive.

You want this, so for a number of reasons,

including not consuming food that is excessively hot

or cold or damaging your gut.

But in general, most people know the temperature of fluid

that they want to ingest

and ingest that temperature of fluid.

So most people, for instance, on a cold day

want a warm or hot fluid.

Does that mean that you’re not going to absorb

that warm or hot fluid?

No, of course it doesn’t.

You’re going to absorb that fluid one way or the other.

So drink fluids at the temperatures

that are to your liking in that moment.

In other words, what you desire in that moment.

And don’t worry so much

about trying to avoid cold beverages

or trying to make sure that you’re always consuming

room temperature water as opposed to cold water.

So now with your understanding of hard water,

soft water, magnesium,

the relationship between magnesium, calcium,

and the pH of water.

And remember our earlier conversation

where we talked about how higher pH water

is actually going to move out of the gut

and into the body a bit more readily

and across those aquaporin channels more readily

than lower pH, more acidic water.

Well, that raises the question

of whether or not all these different forms of water

that are out there, reverse osmosis water,

distilled water, double distilled water,

deuterium depleted water,

alkaline water, as it’s often called,

whether or not any or all of that

has meaningful health outcomes.

Here we can address some of those items pretty quickly.

For instance, distilled water and double distilled water

is essentially distilled of,

that is it has magnesium and calcium removed from it.

So my recommendation would be to not drink distilled water.

There may be specific circumstances

where somebody has very high levels of blood magnesium

or calcium or calcium stores within the body

that would necessitate them drinking only distilled water,

but that seems like a very isolated kind of niche case.

So in general, consuming distilled water

is just simply not necessary.

Now, in terms of reverse osmosis water,

what is reverse osmosis water?

Reverse osmosis water is water

that has been passed repeatedly

through a series of filters

that are designed to remove the kinds of contaminants

we were talking about earlier.

So some of the basic contaminants

like disinfectant byproducts, fluoride,

and some other large and small molecules

that leaves the water ideally

still containing magnesium and calcium.

Although there’s some evidence that reverse osmosis water

can deprive water of some of the magnesium and calcium.

So if you are going to use reverse osmosis filters

and drink reverse osmosis water,

you want to make sure that you’re still getting

the magnesium concentrations present in that water

that we talked about earlier.

But in general, reverse osmosis water is considered safe,

but, and for many people, this is going to be an important,

but very expensive to access.

The reverse osmosis filters require a lot of changing

of the filters, purchasing reverse osmosis water

in its stable form within containers.

These are typically glass containers.

It’s going to be pretty expensive

and prohibitive for most people.

That said, there are a number of people out there

that really like the taste of reverse osmosis water.

They report it as feeling more smooth.

They think of reverse osmosis water as,

quote unquote, giving them energy.

To be quite honest, there’s no direct studies

of the subjective sensation of water in the mouth

and in the gut and its relative health effects.

Again, the smoothness of water as one drinks it

and goes down the gut really has no direct relationship

to the, quote unquote, hardness or softness of water.

I know that’s going to shock a number of you.

You probably think, well, hard water

is going to be hard to drink.

And it turns out that’s not the case.

In fact, many people find that with elevated levels

of magnesium and calcium in water,

it actually tastes smoother or softer in their mouth.

So hard water tastes smooth or soft.

I know it’s all very counterintuitive,

but I think it’s important to point this out

because a number of times you’ll hear or read

about filtering water so that it tastes smoother and better.

And oftentimes that’s happening

because the, quote unquote, hardness of water,

that is the concentrations of magnesium

and calcium are actually increasing.

So if you’re somebody who’s curious

about reverse osmosis water,

and you can afford the filters

or the reverse osmosis water already pre-filtered,

please be my guest, you know, drink it.

I’m certainly not trying to prevent anyone from drinking it.

But there’s no peer reviewed evidence that I am aware of

that conclusively shows that drinking reverse osmosis water

is far better for us than drinking other types of water,

provided the other types of water

are adequately filtered of fluoride

and the sorts of disinfectant byproducts

that we talked about earlier.

So what about hydrogen water?

You may have heard of this or hydrogen enriched water

or electrolyzed reduced water

as a way to access hydrogen enriched water.

All this might sound pretty crazy to some of you.

Now, fortunately for sake of today’s discussion,

we can take a number of the different categories of,

let’s call it unique categories of water

that have been described, including deuterium depleted water.

And by the way, deuterium is something that relates

to the presence of hydrogen ions in water.

And put very simply, water that is extracted from sources

that are closer to sea level

tend to have more deuterium in them

than water that is extracted from sources

further from sea level.

So up in the mountains, for instance,

and from springs further away from oceans.

As you get closer to sea level,

the sources of water separate from seawater

tend to have more deuterium,

which relates to the enrichment

or lack of hydrogen within that water

or free hydrogen within that water.

I warned you, this was all going to sound pretty niche

and that we were going to get a little bit

into the chemistry,

but now I’m going to make it all very simple for you,

at least for the non-aficionado.

Electrolyzed reduced water,

which is a method of using electricity

to alter the conformation of the water molecules

and their rates of movement as well,

as well as so-called hydrogen-rich water

or hydrogen-enriched water or deuterium-depleted water,

all have the property of having higher levels of pH

than other forms of water, such as distilled water,

reverse osmosis water, and generally higher pH

than the kind of water that comes out of your tap,

unless you live in a region where your tap water

has very high levels of magnesium in it,

which does occur in certain regions of the world,

but is not that common.

More typically, the water that comes out of your tap

does not have enough magnesium,

meaning not as much magnesium in it as you would like.

And this, I believe, explains

in a fairly straightforward way

why there is such an appeal of these pH-enhanced

or alkaline waters or electrolyzed reduced water

or deuterium-depleted water.

There are a couple of reasons,

but first of all,

anytime someone is consuming a specialized form of water,

chances are it’s going to be filtered

of the disinfectant byproducts, fluoride,

and the other things that you really don’t want in water.

So already the water is going to be cleaner

than would be coming out of the tap.

So that’s going to indirectly explain

a number of the so-called health benefits,

both subjective and perhaps even objective,

as we’ll talk about,

that can result from consuming these other,

let’s say more esoteric forms of water,

at least not of simple tap water.

However, if you look at hydrogen or hydrogen-enriched water,

you really need to take a step back and ask, what is that?

You know, what are we really talking about?

Because it turns out

that you can create hydrogen-enriched water

by putting tablets of magnesium itself,

small amounts of magnesium, dissolving those in water.

It will give off a kind of gaseous solution.

You’ll see a bunch of bubbling in there.

You certainly want to dilute that tablet

and then consume the water.

And yes, it’s true,

what you’ve heard about and read

from these commercial sources,

you do want to consume that water

within about five to 15 minutes

after that tablet completes dissolving.

Now, why would you do this?

And I should say that I have now started doing this,

not because I necessarily think

that it’s so necessary or so beneficial.

I’ll talk about my experience in a moment.

I did it in anticipation of this episode

because I was researching water

and hydrogen-enriched water and all these alkaline waters.

And what became very clear to me

based on reading a fantastic two-part review,

it’s a very extensive review entitled,

at least the first part is entitled

Electrolyzed Reduced Water,

Molecular Hydrogen is the Exclusive Agent

Responsible for the Therapeutic Effects.

And then there’s a second part to this review.

This is how extensive it is,

entitled Electrolyzed Reduced Water.

Number two, Safety Concerns and Effectiveness

as a Source of Hydrogen Water.

What this review,

which we’ve linked to in the show notes,

points to is that all of the health benefits

of these different forms of water

that you hear about out there,

deuterium depleted, hydrogen-enriched, et cetera,

all seem to boil down, no pun intended,

no boiling included, I should say,

to the elevation in hydrogen that translates into,

and here’s the really meaningful change,

the elevation in pH that occurs

when you hydrogen-enrich water.

Now, there are not a lot of clinical studies

looking at hydrogen-enriched water,

but there are starting to be more than a few.

And one that I’d like to point out

and that we’ll link to was published fairly recently,

which is entitled,

Hydrogen-Rich Water Reduces Inflammatory Responses

and Prevents Apoptosis.

Apoptosis is a naturally occurring cell death

during development and is generally used

to describe cell death of the body.

Sometimes this can be good cell death, by the way,

removing cells that need to be removed.

Again, the title of the paper is

Hydrogen-Rich Water Reduces Inflammatory Responses

and Prevents Apoptosis of Peripheral Blood Cells

in Healthy Adults, a Randomized Double Blind Control Trial.

Now, this paper looked at the effects

of drinking 1.5 liters per day of hydrogen-enriched water

for a period of four weeks.

They did find significant positive benefits

of reduced inflammation,

and they found these changes by way of analyzing things

like interleukin-6 and some of the other interleukins,

which are markers of inflammation.

They controlled very nicely for the fact

that people were still consuming other forms of water

and liquid and coffee, et cetera,

although they made sure that they weren’t consuming

too much coffee and soda

in addition to this hydrogen-enriched water.

But what this paper shows is that indeed,

increasing the free hydrogen in water

can improve certain health metrics in these cells.

And this is in keeping with some of the subjective reports

that people have stated out there,

and that I myself experienced.

I have to say that by drinking hydrogen-rich water,

which I’ll tell you how to do

fairly inexpensively in a moment,

you do get the subjective experience of having more energy,

of feeling better, quote-unquote.

Now, keep in mind, of course,

the placebo effect is a very real and powerful effect,

so it could just be placebo.

Although in this paper,

they did, of course, include a placebo group,

so people didn’t know if they were getting

hydrogen-rich water or non-hydrogen-rich water.

I should also mention that the improvements

in health metrics that they observed in this study

were only observed for individuals older than 30 years old.

Why that is, I don’t know.

The conclusions these authors came to

in terms of how these individuals older than 30

achieved lower levels,

or I should say reduced levels of inflammation,

and improved markers of other aspects of biological function

is that the hydrogen water

improved the biological antioxidant potential

of certain cell types.

And again, the cell types that they mainly focused on

were these peripheral blood cells in this particular study.

Now, how could this be?

Why would this be?

Well, this goes back to our earlier discussion

about reduction in reactive oxygen species,

so-called ROSs,

and reductions in free radicals that can damage cells.

So if all of this is sounding very convoluted,

I can understand why.

However, what I like about this study

and the two reviews that I mentioned a moment ago

is that these studies don’t really say

that hydrogen-rich water is what’s essential.

What these studies really point to

is that the changes in pH of water,

that enhancing the hydrogen in water can create,

is what leads to the enhanced either absorption

and or ability of cells to utilize that higher pH water.

Again, not by changing the pH of the body or of cells,

but simply because higher pH water,

or we could perhaps more accurately state,

less acidic water,

that is harder water that contains more magnesium

and calcium seems to be more readily used

by the cells of the body.

And therefore, it’s very likely that the individuals

in this study were achieving higher

or more efficient levels of hydration.

Okay, so if any of this is confusing,

let me be very clear.

I do not believe that we all need to drink

deuterium-depleted water,

or that we all need to drink electrolyzed reduced water,

nor do I necessarily believe

that we all need to drink hydrogen-rich water.

However, it’s very clear to me

that all these different forms of water are better absorbed

and therefore lead to better and more efficient hydration,

and therefore can reduce inflammation, blood pressure,

and improve a number of other health metrics

because of the elevated pH

that all of these different purification

or water treatment methods achieve.

And that elevated pH, again,

is not changing the pH of the cells and tissues

and organs of your body.

You actually don’t want that.

Rather, that elevated pH is simply making the water

less acidic than it would be otherwise.

So the simple takeaway is this.

If your tap water contains sufficient magnesium

per the values that we talked about earlier,

I don’t think you need to hydrogen-enrich your water.

I do, however, suggest that you at least analyze your water

or look at some of the professional analysis of water

that you can achieve online,

and filter out disinfectant byproducts and fluorides,

et cetera, from that magnesium,

or I should say sufficiently magnesium-containing water.

Okay, put simply, if your tap water has enough magnesium,

filter it, but drink it,

and I think you’re doing just fine.

If, however, the levels of magnesium in your tap water

are not above that value that we talked about earlier,

in that case, I do think,

and I can completely understand why,

enriching the amount of hydrogen in that water

can make that water not only more palatable, right,

give you the sensation that it’s softer or smoother

or more enjoyable to drink

than more acidic water would be,

but also that that water is going to be far more effective

in being absorbed and hydrating the cells

and tissues of your body,

which turns out to be very important for an enormous range,

perhaps every biological function

within your brain and body.

So how can you hydrogen enrich your water?

That actually can be done fairly inexpensively.

I’ve been doing that, as I mentioned earlier,

as part of an experiment in preparation for this episode,

because it turns out that the water

that comes out of my tap has very little magnesium in it

and very little calcium as well.

The way to create hydrogen rich water

is you can simply purchase molecular hydrogen tablets,

which in reality are just magnesium tablets

that dissolve in water and create a free hydrogen

that can interact with the other water molecules.

Now, the chemistry behind it has been substantiated

and I’ll provide a link in the show note captions

to a paper that gets into some fairly extensive detail

about the way that having an additional hydrogen

in your water can adjust the flow of electrons

and the adjustment of free radicals.

But keep in mind, again, this is all through increases

in the pH of your water.

And please keep in mind that you can’t simply take

any other or any old magnesium tablet or capsule

and put it into water.

The configuration of the magnesium in these capsules

and tablets is such that it allows a rapid dissolving

of the tablet and the activation of the free hydrogen

that can interact with the water molecules.

Again, there are only a few scientific studies

exploring the real biological effects

of these activated hydrogen waters.

The dissolvable tablets are the far less expensive way

to go than purchasing pre-packaged

and sealed hydrogen water.

In fact, I don’t recommend those brands

because they are quite expensive

and it’s not clear how stable the activated

or free hydrogen is in those waters.

In any case, this is certainly not something

that everyone needs to do.

I mention it because I have had a good experience

with it myself.

I also will mention again that I have no business

or affiliation to any of these products.

I’ll provide a link to a few of them

in the show note captions for those of you

that want to experiment.

And indeed, that’s why I’m telling you this.

For those of you that want to experiment

with raising the pH of your water

without having to purchase what is ordinarily

quite expensive, higher pH water,

you can do this with these dissolvable magnesium tablets.

My experience with them has been quite good.

In fact, I plan to continue to use them

once or twice a day.

This is not the sort of thing that you need to do

in all the water that you drink.

I want to repeat, even if you go down this path

and you find that you really like

the activated hydrogen tablet approach,

it is not the case that you want to put these

in all of your water.

And you certainly don’t want to put them

in carbonated waters of any kind

that will lead to a lot of gastric discomfort,

nor do you want to put them into hot liquids of any kind.

So again, this is the sort of thing that you do once

or twice, maybe three times a day,

and you can find out for yourself

and sort of measure subjectively

whether or not you like the experience

and whether or not you, quote unquote, feel better.

Now, earlier in the episode,

we were discussing structured water

or this fourth phase of water.

I know a number of people out there are curious

as to whether or not ingesting structured water

is somehow better for us

than ingesting non-structured water.

All I can say about this is that

it is a very controversial thing

to suggest that structured water

is somehow more biologically effective

or better for us than non-structured water.

There are a number of different ways

that one can create structured water.

They involve some pretty extensive

and expensive at-home systems,

ranging anywhere from a couple of hundred dollars

to a couple of thousand dollars or more.

To be quite direct,

when one goes into the peer-reviewed scientific literature,

one will not find, that is,

there is essentially no real evidence

that ingesting structured water

leads to any specific desired biological outcomes.

Now, as I say that, I’m sure there are people out there

who have still had tremendous experiences

ingesting structured water.

Whether or not that’s due to a placebo effect

or a real effect of ingesting structured water isn’t clear.

Just to give you a sense of what my stance is

on things like structured water,

I think that they are interesting and intriguing,

but as a scientist,

in the absence of any quality peer-reviewed data at present,

I can’t really suggest that people go out

and start ingesting structured water,

nor that they adhere to the claims

that structured water is going to be really, really good

for them compared to other forms of water.

That said, I do think that there’s an interesting

and open space for further exploration

of the biological effects of structured water,

given the fact that structured water does exist,

I don’t think anyone debates that,

and the fact that the different structures of water

in this fourth phase of water, as we’re calling it,

has been shown to interface with solids

and other aspects of liquids

and can do so within organelles of cells,

so different components of cells

that control different functions, including mitochondria.

I think there’s a potential there.

Whether or not there’s a promise there

is another question entirely.

So I don’t want to shut the door on structured water.

I think this is an open question

that I hope there will be more data

to answer those questions in the not-too-distant future,

and meanwhile, if any of you are aware

of good clinical studies exploring the biological effects

of structured water in either animal models or humans,

please put those references in the comments on YouTube,

because I’m very curious as to how this area

of biological effects of structured water

is evolving and continues to evolve.

So today we discussed water, and admittedly,

we went into a lot of detail about the physics

and chemistry of water in its various forms,

and we talked about hydration,

because I think that’s the main reason

why many of you are interested in or concerned about water.

We also talked about contaminants in tap water,

which unfortunately do exist and are very prominent

in essentially all regions of the world,

so please do get some information

about what’s coming out of your tap.

I also want to throw in one other piece of information

that’s really critical that I learned about

when researching this episode,

which is the quality of water that comes out of your tap

is not just dictated by the source that it comes from,

external to your home or apartment,

your pipes are also important,

and that filter or that little mesh

that sits at the faucet head is also very important.

Most people don’t pay attention to that,

but it turns out that a lot of debris and contaminants

can be derived from that little filter

that most people just simply aren’t cleaning often enough.

So here, I’m not trying to tell you that the metal

or the plastic that that filter is made of is a problem.

More often than not,

contaminants are showing up in water

because people aren’t cleaning those filters often enough.

And in fact, prior to researching this episode,

I didn’t ever think to clean that filter.

I looked underneath my faucet,

and while that filter didn’t look

particularly filled with debris,

I did find that when I took it off

and I looked at the other side,

there was quite a lot of debris.

So if you are going to consume tap water,

you definitely want to consider the source,

the pipes in your building or apartment,

the ones that lead right up to your glass or jug

that you would put that water into,

and also that mesh that that water passes through

as it goes into that glass or jug.

We also talked about how much water to drink.

I hope that we finally resolve that question.

For those of you that have been wondering about that,

the Galpin equation is a wonderful approach

to how much water to consume during exercise.

And by providing these other formulas

of about eight ounces or 240 milliliters of water per hour

for the 10 hours from waking until post-waking on average,

remember it’s averages,

you don’t have to consume them every hour on the hour,

and no need to be neurotic.

Hopefully you can achieve better levels of hydration,

which we know can lead to reductions in blood pressure,

improvements in appetite, mood, and focus.

And I really think that it’s the improvements

in cognitive focus and physical ability,

both endurance, strength,

and other forms of kind of readiness in the body,

readiness to perform work in the body,

that really are best supported by the hydration literature.

And then of course,

we went through the different forms of water

that you hear about out there,

and addressed which ones are going to be beneficial or not,

and perhaps more importantly,

why any of them would be beneficial.

Thinking about that from the perspective of biologists

and the chemistry of water.

And I do hope that by arriving at this point

in the episode now,

that you have a much better understanding

of the chemistry and physics of water,

and the way that water can powerfully impact your biology.

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