43. Endocrine System Basics and Care w/ Dr. Claire Merrifield

Episode Transcript
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(00:00):
Well, today discussion is with Doctor Claire Merrifield and all
about the endocrine system. And we're really going to focus
on kind of the structure and function of the system and then
be dispelling some things about the system and and how we can
make systems thrive. And it's one thing to talk about
different pathological conditions with different

(00:22):
systems, but also how do we makeit better and how do we help
people and, and in this case, especially clients, colleagues,
and other professionals. So, Doctor Merrifield, thank you
so much for joining me for this.You're very welcome, I really
appreciate you having me on the show.
Most definitely. Let's just jump into it.
So the endocrine system, let's just start with the basics.

(00:44):
Let's hit the basics first because I think as you and I
were discussing that a lot of people jump into more
complicated issues, but let's hit the basics first on this
system. Yes, I think to start with,
let's talk. The endocrine system is
essentially a series of glands which are in various organs and
structures of the body which produce hormones.

(01:07):
So if we start to think about what hormones are first, so the
hormones are chemical messengers, OK, That's all they
do. They tell one part of the body
to do something. So we've got the endocrine
system is a, is one of our main communication systems in the
body. We also have our nervous system
and they they do work together. So it's important to just

(01:28):
mention the nervous system briefly.
Now the nervous system is kind of how we interact with the
world directly. So it's how we see something and
we might move away from something that's coming towards
us quickly, or we might touch a hot stove and move away quickly.
The whole main system, the endocrine system is a, a slower

(01:49):
system than that. You can think of it almost like
posting a letter rather than sending an e-mail.
So we have hormones that produced in various parts of the
body that move around in the bloodstream and communicate with
different parts of the body, telling it what to do.
Now. It's really fascinating kind of
revising this topic for this show because it just makes you

(02:12):
realise how amazingly complicated and wonderful the
body is and how things work, right?
So some hormones aren't just produced by one part of the
endocrine system. I think that's really important
to know. So some hormones can be produced
by different parts of the body. Hormones work on different parts
of the body. So they may not just work on on

(02:34):
one part of the body to do one thing and hormones interact with
each other. So one hormone might tell
another hormone at might tell another gland to produce a
hormone, which might then tell another gland to produce another
hormone, which might then tell the original gland to stop
producing that hormone to, to sort of start the chain, if that

(02:57):
makes sense. So just wanted to lay out a
little bit about the complexity of hormones and hormone or
control before we kind of get started.
So I thought I'd talk about the endocrine system and from top to
bottom, that's just one of the easiest ways I can think of to
explain it. So actually a lot of our
hormones are produced or the signal to produce them is in the

(03:21):
brain. So the hypothalamus is an area
of the brain. You can think of that almost
like our control centre or thermostat of the brain.
So it regulates things like our temperature, our mood, our
libido, whether we're hungry, thirsty, whether we feel full
and stop eating. So it's a really, really
important part of the brain and lots of the signals that produce

(03:44):
hormones and the rest of the body come from there.
In particular our stress hormones, our sex hormones and
our thyroid hormones, which really regulate all of our
metabolism. So you're hypothalamus sits
within your brain. It's attached by a little stalk
to a gland called your pituitarygland.

(04:04):
Now that's a little pea sized gland that sits just behind your
the bridge of your nose, behind your eyebrows.
And I'm talking about where it is because it actually sits
directly below your nerves that conduct your vision to your
brain. So your optic nerves, and now I
don't know if you know, but yourleft eye connects to the right

(04:27):
side of your brain and your right eye connects to the left
side of your brain. So your nerves that go from the
back of your eye actually crossover.
And there's a point that cross, which is directly on top of
where the pituitary gland sits. And that's relevant because
quite a lot of the time problemswith hormones can stem from a

(04:48):
growths in that pituitary gland and that can cause problems with
our vision. So if you ever notice anybody
say that they've got things liketunnel vision or they're
noticing gaps in their vision, that's just a really important
sign to get checked out, making sure you get your visual fields
checked and possibly asking yourdoctor for some blood work.
OK, so your pituitary gland is really important.

(05:09):
So that produces hormones which tell other glands to produce
hormones for the most part. The exception to that is
prolactin, which is a hormone that tells breastfeeding mothers
to to produce milk basically. So moving down, we then have our

(05:33):
thyroid gland. Now that's a butterfly shaped
gland that sits at the base of your neck, just above your
collarbone. It produces thyroid hormone.
So thyroid hormones, if you've heard of them, they are your
main metabolic regulator. So they work on pretty much
every cell in the body and tell it essentially how fast to be

(05:54):
acting and how fast to be moving.
Because of that, it's really important for generating heat
and generating energy. And we can talk a bit more about
thyroid hormone later because the symptoms of problems with
your thyroid are really widespread and lots of people
will have them without necessarily having problems with
their thyroid hormone. We've got your hypothalamus,

(06:18):
that area in your brain that kind of senses what's going on.
That communicates with your pituitary gland.
Your pituitary gland then communicates with your thyroid
to produce thyroid hormone. At the back of your thyroid
gland, you've got 4 little glands called your parathyroid
glands. These have nothing to do with
your thyroid hormones at all. They actually help produce

(06:41):
parathyroid hormone, which is related to calcium balance in
the blood. Calcins are important for muscle
contraction, so in particularly important for things like that
your heart's beating. So it's really important to make
sure your levels of calcium are stable and your parathyroid

(07:02):
hormones will produce a hormone called parathyroid hormone.
Sorry, parathyroid glands will produce parathyroid hormone,
which tells the rest of the bodyto release and absorb calcium.
Then if we move down the body, we've got quite a lot going on
with the endocrine system in theabdomen.
So the gut actually, although wetend to think of the gut mainly

(07:24):
as being related to digesting and absorbing food, part of the
way it does that is by endocrineaction.
So we have entero endocrine cells, they are cells within the
gut, the gastrointestinal tract that tell our body to do various
part things related to metabolizing food.
So in response to having glucoseor amino acids or fats, they

(07:49):
will signal to different parts of the gastrointestinal tract to
do different things. For example, if you have a load
of fat that comes through into the small intestine, that will
produce a hormone called cholecystic kinin, which create
which tells the gallbladder to contract and squirt a load of
bile into their small intestine.That's really important

(08:11):
absorbing fat. Now you've probably heard of a
lot of gastric peptides because we've spoken because lots of
people are taking medication nowlike we go V and Monjaro now
they are basically fake synthetic versions of some of

(08:31):
our our gastric hormones that make us feel full.
So but they're really effective in weight loss.
OK, so so there's lots of different cells within the
gastrointestinal tract which produce various different
hormones which are really important for digesting and

(08:52):
absorbing our food. Another really reported organ is
the pancreas, which sits kind ofbehind the gastrointestinal
tract. The main hormone produces is
insulin. So that will produce insulin in
response to glucose levels in the blood.
So if glucose levels go high, weproduce insulin.

(09:12):
The insulin tells muscle cells and the liver cells to take that
glucose out of the bloodstream. Then when glucose levels fall,
that stops the insulin being produced anymore.
Now there's hormones within the gastrointestinal tract that as
soothing as they sense carbohydrate or glucose will
actually also tell the pancreas to to produce insulin.

(09:35):
So it's almost free advising thepancreas that we're about to
have a meal. So that can really help with
reducing spikes blood sugar. We've also have the kidneys, so
these are two bean shaped organsthat sit at the back of our rib
cage. Most people know about the

(09:56):
kidneys for producing urine, so our waste product, but they're
also quite important for producing hormones and they
produce really three main hormones.
So one of which is actually related to calcium balance.
So when we so it actually activates vitamin D in the
kidney. So when we have low levels of

(10:18):
calcium, it signals our parathyroid gland to produce
paragyroid hormones that then tells our kidneys to turn
vitamin D, which fill produce inour skin from the sun or will
take as a supplement. It will tell our kidneys to
activate that vitamin D. Now active vitamin D is a

(10:39):
hormone that then tells the intestine to absorb more
calcium. So it's quite a clever mechanism
with multiple different hormonesat play.
You've probably also heard of EGPO, but that's produced by the
kidneys. So that is erythropoietin.
So that is a hormone that tells the bone marrow to produce more

(11:00):
red blood cells. Now it will do that normally in
response to not having enough red blood cells or oxygen in the
bodies from conditions like anemia or being altitude.
But we may have heard of it or your guests, your listeners may
have heard of it because some people, you tend to use it for
doping. So elite cyclists, for example,

(11:22):
use EPO as a doping agent to increase their red blood cells
and increase their efficiency. It has a negative potential side
effect that it can make the blood very thick and predispose
it to blood clots and, and unfortunately that has happened
with some elite athletes. So it's just a kind of warning
of how important what hormones can be and how what can happen

(11:42):
if we take them inappropriately.Now on top of your kidneys, you
have your adrenal glands. So those are really important
for producing other stress hormones.
So they produce adrenaline, which you get in your fight or
flight response, and cortisol, which is your longer acting
stress hormone. Cortisol is really important in

(12:04):
general in the body for for daily regulation, but we know
that excess prolonged cortisol due to unrelenting stress causes
a lot of problems with the rest of the body, partially because
of its interaction with other hormones.
So we've gone down most of the body, we've got the the sex
hormones, the last main bits to talk about.

(12:27):
So men, the product primary sex hormone in men is testosterone
and that's produced by the testicles in response to signals
from the pediatric land, in response to signals from the
hypothalamus. OK, so testosterone probably
lots of your listeners will know, but it's a very important
hormone in men. It's important to muscle

(12:48):
building energy, libido and it can gradually decrease as we age
and often men might replace it when they get older if they're
experiencing symptoms or if their testosterone levels are
low. Women, lots of their sex hormone
is produced by their ovaries. So women of childbearing age
will produce oestrogen and progesterone in response to

(13:10):
signals from the pituitary glandin quite a complicated dance
throughout their throughout their menstrual cycles.
We don't have to go into that indetail, but suffice to say that
it's very important for fertility.
Obviously, we have to kind of coordinate releasing an egg at
certain times of the month. And estrogen is important for

(13:31):
for lots of other functions likebone health and cardiovascular
health as well. Now we've sort of talked through
most of the major glands in the body, but it's worth also
mentioning something that we didn't used to know about, which
is that fat is a really important part of the endocrine
system. Now.
We used to sort of think that fat was pretty much in a just a

(13:53):
kind of storage unit for energy.But we now know that fat is
extremely metabolically active. There's different types of fat,
brown and white fat, white fats,much less metabolically active.
But it's important to know that a fat produces hormones and
those hormones regulate appetiteand other things.
So our fat produces something called leptin which makes us

(14:16):
feel full. So theoretically the more fat
you have, the more full you feeland so the less you tend to eat.
But unfortunately in conditions like obesity where people have
lots and lots of fats cells, they produce so much leptin that
they may stop responding to the the signals of the leptin and
end up essentially overeating ornot not realising that they

(14:40):
don't need to eat. So it's quite a, quite an
interesting system that is very,very delicately balanced.
So hopefully I've given you a bit of a general tool and
through the body of the endocrine system, I know there's
a lot, I mean there's 1 / 50 allknowns.
We won't get more in detail, butjust to give you a bit of a
flavour of the complexity of it.Gosh, that was fantastic.

(15:03):
Doctor Merrifield, really appreciate that and all the
folks who are going to listen tothis are going to are very
appreciative. I guarantee you we're going down
through there. So let's go back through.
There's a lot to digest there. And the way I want to digest
this is going through probably what's more common to most
students, professionals, colleagues.

(15:26):
Let's talk about the thyroid gland.
So I can't tell you how many times I've heard of clients talk
to me about the lack of functioning in their thyroid
gland and that this is a very large problem in terms of weight
loss, different conditions related to that.
So in your experience and in your education, how much of A

(15:47):
role is this playing in terms ofweight loss?
And in reality, I guess, I mean,I think there's just so much
information with this and how much can we attribute not having
significant weight loss to thyroid dysfunction?
Yeah, that's a great question and it's so interesting, isn't
it? Because when I was learning

(16:09):
about the thyroid gland as a medical student, I remember
looking at the symptoms of low functioning thyroid, which just
for the benefit of your audience, if your thyroid is not
working, you typically feel tired, it's hard to lose weight
or or you're sort of putting on weight and you don't really want
to. Sometimes you're a bit
constipated, often feel a bit cold, sometimes your skin is a

(16:32):
bit dry, your hair not might be a bit lackluster.
Lots of sort of very vague symptoms that lots of people had
and I was 100% convinced that I had no thyroid.
I was, This is why I don't feel bright and why I'm not skinny
mini. And lo and behold, I tested my
thyroid is perfect, perfect thyroid function.

(16:53):
And I think it's extremely common that people will read a
laundry list of things that you know, the low thyroid hormone
cause and think, well, that mustbe it.
And often they have a perfectly normal thyroid.
It is a common cause of endocrine dysfunction.
And it tends to get more common as you get older.

(17:13):
It's more common in women. So sort of around 40s to 50 that
can be as as often as 10% of women.
So it is really important, particularly women who are kind
of around perimenopausal age, it's very, very important to
check your thyroid levels because 'cause sometimes the
symptoms to perimenopause can get confused with low thyroid.

(17:34):
So it's important in that age group.
It tends to be less common in younger people, but it can
happen. And I do recommend that people
check their thyroid on a regularbasis because it's so common.
However, if you tested your thyroid and it's fine, it's very
unlikely, then that's the cause of your problems.
There are lots of other things that that affect weight loss

(17:57):
stuff and nothing to do with that.
And I think we're often looking for a quick fix or a pill that
can help us. You know, I'm not immune to
that. I think we all, we all want that
generally by particular when it comes to weight loss.
It's not a not an easy thing to to do.
But yeah, I think we we sometimes over attribute

(18:19):
problems with thyroid to that. Yeah, I again, I don't want this
to sound like I'm saying that this is oh, just everyone thinks
they have a thyroid issue. But just in my practice over 20
something years, it's probably the most common hormonal issue
to discuss along with what we will discuss is a sex based

(18:41):
hormones as well, which is getting a lot of publicity,
especially during perimenopause,menopause, things of that
nature. But just a lot of attribution of
lack of weight loss to the thyroid, lack of thyroid
functioning and that This is whythis isn't happening versus
looking at well, a big a pantheon of effects of things

(19:04):
and modifiable lifestyle behaviors for that.
So in the same element when talking about low functioning
thyroid, what are some things that can be done to increase the
functioning of the thyroid so that it's more optimised versus
even just being normal? What?
What can we do for that? So I mean, I think the reality

(19:26):
is that if you actually have a problem with your thyroid glands
such that it isn't producing enough thyroid hormone, usually
you need to actually take take medication to to solve that.
You know, if you have an autoimmune condition, which is
the most common reason for people in the West to have low
functioning thyroid, then then you need to take a replacement.
There isn't really an alternative for that.

(19:49):
There are things we can do in our lifestyles to support a
healthy thyroid function, but that's all it does is support
our natural function. It doesn't.
It's not going to increase your thyroid levels if you if you
don't have a problem. And so, you know, nutrition is
really important for thyroid function because the thyroid

(20:10):
needs quite a few different things in order to produce
thyroid hormone, particularly elements like iodine, selenium,
magnesium. And those are typically present
in a, in a diet where you have quite a whole food diet where
you include meat, dairy, fish, nuts and legumes into your diet.

(20:34):
If you have a very restrictive diet, then like, or you're a
vegan, it might be worth supplementing.
So taking just a standard multivitamin supplement and
possibly even protein supplements to make sure that
you've got enough kind of building blocks for your for
your thyroid hormone. But it's certainly not necessary
to go on a really extreme diet for it.

(20:57):
And, you know, think a lot of people are aware that iodine is
important for thyroid function and sometimes they might take
supplements which contain iodine, but that's actually a
really bad idea because too muchiodine inhibits thyroid hormone
production in a similar way to not enough.

(21:18):
So we have to be really careful with the amount of iodine that
we have and things like seaweed supplements that can actually be
quite dangerous or cause problems with the thyroid.
Now is very easy for people to come up with a specific thyroid
health plan or something along those lines.
And, and I, I struggle with thata bit because, you know, we can

(21:42):
do things, as I've said, to optimise our bodies own
production of it, that there's not a huge amount else that we
can do to, to kind of maximise the production.
I mean, I don't know what your experience of of that is or what
what you've found people doing. No, I mean, I, I would, I would
say most of my clients who have had, you know, thyroid

(22:03):
dysfunction are on medication for that.
So I was just curious from your point of view, what were some
other ideas about it? But as I think, you know, the
point of this is really get solid information out there.
There's just so much misinformation about different
hormonal levels and people throwthe word hormone out very like

(22:25):
just casually, oh, this hormones, always my hormones,
this is hormone, this hormone and say, OK, well, let's discuss
what these hormones actually do for that.
And so before we move on to the next thing about cortisol,
because again, another common discussion, remember stress
cortisol, what's maybe the biggest, I guess you could say

(22:47):
misinformation related to the thyroid that you hear or you're
like, wow, this is not accurate information related to thyroid.
That's a good question. I think some people are slightly
mistrustful of thyroid function testing even though we know it's
very good. And I think that's because lots

(23:08):
of people experience the symptoms of low thyroid without
it being caused by the thyroid. And I think there's a
potentially a desire, as we've said, for, for there to be a
problem to fix, for there to be a hormone that's out of balance
that we can correct. I could probably that's one of

(23:30):
them. And, and I don't know, I hear
this term a lot on social media,the idea that we can balance
hormone and that we have a lot of control over these things.
And the reality is that if we have a condition that affects
our ability to produce, I would hormone, there's not a huge
amount that we can do about it other than take medication.
And, and that's OK. And the medication works and
it's good and it's all improved people's lines.

(23:51):
So I think we have to, we have to be mindful of how much
control we actually had over a lot of these conditions.
Do you ever run into any issues with people who are resistant
about medication for any of these things?
Yes, yeah and yeah, it's a problem because it it really

(24:13):
does affect a lot of a lot of your life and and what's you
know, something that's quite common condition is called
subclinical hypothyroidism. I don't know if you're counts
have ever mentioned anything like that.
So this is a condition where essentially the the hormone
chain in the brain works that you have TSH.
Thyroid stimulating hormone is produced by your pituitary gland

(24:35):
that then tells your thyroid hormone to produce thyroxine.
When you have enough thyroxine in your blood, that tells the
pituitary gland to stop producing TSH.
OK. So in a normal person who has
good thyroid levels, you will have a relatively low level of
TSH and a relatively high level of of thyroid hormone T3T4.

(24:57):
When we do testing, we usually test both TSH and T3T4.
Now some who's got proper problems with their thyroid, so
really low thyroid, they will have a high TSH and a low
thyroid hormone. So the thyroid hormone isn't
telling the pituitary to stop producing the TSH.

(25:18):
So that's a, that's a definite, you've got low functioning
thyroid hormone, you thyroids, you need medications.
But we also see something which is probably a precursor to full
blown hypothyroidism, which is where you have a normal level of
thyroid hormone, but high levelsof TSH.
So the thyroid hormone almost isn't working properly to tell

(25:39):
the, the, the pituitary gland tostop stimulating the thyroid
gland, if that makes sense. Now that's quite a difficult
thing to treat because what we typically say to patients, if
it's, if that's really high, then we would do a trial of, of
treatment. But if it's only moderately

(25:59):
high, we would only try treatment.
So to try taking thyroid hormoneif you had symptoms, which we've
explained that probably everybody has symptoms, no
thyroid. And the, The thing is, I think
once you start taking this medication, you're pretty much
taking it for life. So I think people are resistant
to that idea. But it's important to be aware

(26:22):
that the thyroid, if you do havelow thyroid or borderline low
thyroid, it can often develop into, into low thyroid problems
later. And it has all sorts of
implications on the rest of our body.
And our metabolic health can affect our cholesterol.
So we can have high cholesterol,which then increases our risk of
heart disease and things. So it's it's just, it is

(26:42):
importance. Take it if you need it, but it's
worth a trial of these things tosee if that's really the cause
cause of your symptoms. Outstanding, yes, God loves
that. Not with straight actually I
have I know several clients who are going to listen to this and
be like, whoa, like I think you know where there's, I think
current times too. There's just, there is a faction

(27:04):
of people who are just very resistant to any medication and
for some reason they've gotten in their mind that this is bad,
medication is bad, and that everything is capably capable of
being taken care of through ulterior means.
But there are some realities to certain conditions.

(27:25):
And so I, I appreciate you beingvery honest about that.
And what you'll find often is that that those sorts of people
that can for people will have absolutely no problem taking all
of the supplements. They will be taking powders and
tablet, they'll be rattling withsupplements, but a kind of
pharmacological medicine, they will have a problem with which

(27:45):
it doesn't really make sense, doesn't it?
If you're if you're kind of happy to take medication to or a
supplement, supplements work often in very similar ways to
lots of, lots of medicines. And I think we have to be
realistic, you know, there's, wecan do as much as we can in
terms of our lifestyle, but sometimes our genetics don't
allow us to be as healthy as we could be.

(28:06):
And we've got really brilliant medications for some things that
work really well. We should not be afraid of using
them and not feel like a failureif we have to use them.
I think that's really important.I think it's not your body
failing or you failing your body.
It's nothing that you've done to, to kind of 'cause this, it's
just the body is extraordinarilycomplex.

(28:27):
There's so many things going on all the time and we're in
really, really lucky that it works well most of the time for
us. So I think we need to, you know,
take take the support where it exists and where it's good and,
and do what we can for the rest of that.
I always tell my students especially that the body is
incredible with all these homeostatic mechanisms that are

(28:47):
trying to occur to balance theselevels out and all the different
systems that are occurring in order for you to have
essentially neurotypical behavior on a regular basis is
astounding. It's it's truly astounding.
Astounding. And I think we we are, there's a
camp of people and this will go into sort of dispelling myths

(29:07):
that that almost feel like it's incumbent on us to get involved
in that and try and try and you know, it's our United States.
We've got no idea what's going on.
It's OK, it's good. And that we need to stay well
alone. It kind of reminds me of, I
think when, when the human gene genome was mapped and there was

(29:30):
a lot of excitement about, well,you know, now we're going to be
easily be able to essentially like a light switch, turn on and
turn off genes and we're better solve all these things.
And what it did is just create more questions and, and to me
create more respect into the thevast complexity of what has to
happen, kind of the interconnectedness of all the

(29:52):
systems together that it's the system is so complex, it's
almost mind boggling. It's mind boggling and sometimes
I wonder that we're actually able to comprehend it at all.
And certainly, you know, my, my research background is, is the
gut microbiome that is beyond mind boggling.
There's no way we're ever going to fully understand that in our
lifetime, I don't think. But you know, what's interesting

(30:15):
about the genome is I don't knowif you remember this from back
when you were learning about this at school, but we always
used to call bits of bits of thegenome junk DNA because it has
been to code for gene. And obviously now we know that
that's really, really important.And I think our understanding of
all of these things is just exploding at the moment.
And I think people who haven't necessarily got the scientific

(30:39):
or the medical background shouldbe quite aware of the message
that they're giving on, on social media if they're, if
they're in a position of being an influencer or something like
that. Because people will listen to
influencers, unfortunately, a lot more than they'll listen to
scientists and doctors. And, you know, they people have
got a responsibility to not givemisinformation out.

(30:59):
And if you don't necessarily know what you don't know, you're
dangerous. Most definitely.
I had another man. The questions just popping up
here for me. I have a quick question related
to how much of the dysfunction in the endocrine system is
related to heritability. Yeah.

(31:21):
That's a really good I question.It's often not that common in
all honesty. The, I would say that there are,
there are a lot of genetic defects which occur within parts
of the nation, the endocrine system, they're not often
heritable. There are probably, and you, you

(31:41):
wouldn't have heard of things like thyroid disease is often
heritable, but that tends to be because autoimmune disease is
heritable and autoimmune diseaseis the most common cause of, of
thyroid dysfunction. But when you think about how
complex the endocrine system is,you've got to have a gland to
produce a hormone and it's got to go to another gland attached

(32:04):
to a receptor, get into the cell, do something else,
probably produce another hormone.
There's all sorts of genetic defects that can happen along
that route. And lots of those defects just
aren't compatible with life. So we've sort of evolved quite
well to not have very many hereditary and decline issues.

(32:26):
I'm not saying there aren't any.I would say it's not the major
thing that you think of when you're thinking about that.
It is. It is sometimes related to
genetic defense, but often just things that occurred during the
course of life. So it, it sounds, I mean it
sounds like I don't want to put words in your mouth, but it
sounds like the heritability is is lower and and just generally

(32:49):
speaking. Yeah, It's not often the case
that you'll have say somebody, for example, I was just looking
at this, looking through my hormonal things earlier.
There's there was a picture of two identical twins.
One of them had acromegaly, which is or gigantism, which is

(33:11):
an overproduction of growth hormone.
So that's not related to genetics.
They're genetically identical, but one of them has just had a
spontaneous production of of thegrowth hormone.
And what you find is that in these cells that are quite
complex, then they're producing lots, they're doing lots.
They can just start overproducing things.

(33:34):
And just by themselves, it's, it's, yeah, I would say it's,
it's less important than other factors.
Love it. Great information.
Let's move on to cortisol. Again, I'm trying to focus for
the audience purposes on things you guys will know mostly that
you're like, oh, this is kind ofmore pop culture discussions

(33:54):
that maybe you've been fed a lotof information about it.
And certainly cortisol levels have been a huge talking point
and stress. So let's dive deeper into that
in terms of what is. Let's start first with this part
to spelling some aspects about cortisol production related to
health and well-being, stress levels, weight loss, the whole

(34:15):
deal with that. So cortisol is a really
important hormone. We actually can't live without
it. People who don't produce hormone
and cortisol have to take steroid hormones, otherwise they
essentially die. They can't handle it if they get
an infection in particular. Now cortisol itself, similarly

(34:37):
to thyroid hormones, so it's produced, the signal starts in
the hypothalamus, goes to the pituitary and then goes to the
adrenal glands and produces cortisol.
We produce cortisol every day. We typically have more in the
morning first thing when we wakeup and it's a kind of, so it's

(34:57):
important for lots of different things.
It stops the immune system overreacting.
So it's actually anti-inflammatory, which might
surprise some people who think that cortisol is all bad and
inflammation is all bad, but never, never.
It's quite that simple and it's important for regulating our
blood pressure, which is probably why it's high in the

(35:17):
morning. So it kind of allows us to get
up out of bed and get up and do things.
So really important just for sort of general life and it is
sort of interacts with lots of other hormones.
Now we know that when you're exposed to stress now be that
intense exercise, pain or psychological stress, you get

(35:42):
extra cortisol being produced. Now that can be protective in
lots of ways. And actually we know that if you
don't have enough cortisol, you actually can't handle stress.
Like for example, you couldn't handle being exposed to a cold
for a long time, but you couldn't handle a really intense

(36:02):
infection. So it's actually helps us a bit
in our stress response in itselfis not necessarily that harmful
apart from when you get it in high doses all the time.
And now part of that is because you imagine that because it's
your stress hormone, right. So if almost preparing you for

(36:25):
action. So imagine you're walking across
the African plains, you spot a tiger and you go Wharf or get a
load of adrenaline. So my fight, fight or flight
kicks in. But also I'm getting a lot of
longer acting cortisol and it's mobilizing my body, getting it
ready in case I need something. So it's essentially it stops the

(36:48):
action of insulin. So it stops you taking glucose
from the bloodstream into the cells.
Now long term that's obviously quite bad for your health, but
short term that's what you need if you're in a stressful
situation because you need lots of energy to be available for
your brain in case you have to run all day from this tiger and
you haven't got anywhere to stop, you can't eat anything.

(37:10):
And it also mobilizes amino acids in your bloodstream so
that you can repair cells if youhappen to injure yourself.
So it's a very important mechanism, but because we are
living in a time of excess stress, we're not very good at
managing large stress. We are often in a constant state

(37:34):
of having too much cortisol in our bloodstream.
And because that affects things like our insulin levels and the
action of insulin, it tend typically effects our weight.
OK. And you'll probably have heard
that cortisol is really kind of instrumental in, in almost
telling our bodies where to store fat.

(37:54):
So the healthy fat, which I'm sure your listeners know about
is the subcutaneous fat. It's what's under our under our
skin. We need that.
It's important. It's acts as our kind of fat
reserve. But then you can also get fats,
visceral fat, which collects around the organs and around the
tummy. And that's typically less
healthy. It has a much more kind of

(38:16):
aggressive and decline action and is often quite pro
inflammatory in itself. So we don't want visceral fats,
but cortisol. High levels of cortisol.
Too much cortisol will promote the storage of fat around the
tummy and make it harder to shift it as well.
I mean, awesome. I, you know, I think the
anti-inflammatory aspect of cortisol is going to be very

(38:37):
surprising to a lot of people, but the prolonged exposure of
cortisol sounds like what you'resaying is ends up having a net
negative effect in that area. That's.
A negative effect, Yeah, absolutely.
And, and it's, it's probably thehormone that is most under our

(38:58):
control, I would say, because obviously the stresses that we
cut ourselves in, you know, if doing lots of high intensity
training or really intense exercise can increase our
cortisol level. So we have to be mindful of that
if we're very stressed as well. And it's, and it's sort of
something that I talked to my clients about balancing

(39:20):
psychological stress with the stress that you're putting
yourself under through other means.
Obviously exercise is really, really good for us, but it does
create stress on our bodies, which which causes cortisol
release. So if you happen to be extremely
stressed, I would say take it easy on your, on your movement
that day. It's it's something that you
have to kind of balance what else is going on in your life.

(39:42):
But it is under control for a lot of the time, even though we
don't feel like it. I would say that we don't feel
like it part is, I think I hear that the most from especially
students who at least the institutions I work at, the
students are parents. They are going back to school or

(40:04):
they're younger parents or they're taking care of family
members and. They're, they are under a
tremendous amount of life stress, we'll put it this way,
and struggle to balance that with the demands of school and
family and all those things. And trying to get them to
recognize that, you know, studying under this level of

(40:25):
stress and, and learning information actually could be
really counterproductive for that.
Yeah, it's pretty bad for your memory and it makes you eat
more. So you know, there's all sorts
of negatives to it. And I can deadly relate to that
because I studied medicine as a graduate, which in this country
is not common. I know that you do that in the
States all the time, but you know, financially stress

(40:51):
related, it was, it was massive.And I came across mindfulness
when I was doing my medical training and somebody
recommended a book to me called Finding Peace in a Frantic
World. And it was just the best thing
I've come across. It's £10 that could potentially
change your life if you're experiencing stress.
And I actually went on to train as a mindfulness teacher of the

(41:12):
back of that because I just think it's so great for helping
us manage stress. It's just really important for
my health. And it doesn't take long.
It's not something that you haveto commit hours and hours to.
It's sort of 10 minutes a day and just a bit more awareness on
your in your day-to-day life. But yeah, I can totally

(41:33):
empathize with the students who are expecting that.
But there are lots of things that we can do to reduce stress.
We just have to make a choice that our health is more
important than whatever else is going on.
I'm. Going to throw a little bit of a
curveball here. I know we didn't talk about
this, but you're like, Oh no, what's this?
It's, it's in the ballpark here,but and, and, and inflammation,

(41:57):
a little more discussion on inflammation.
And it seems like the current data are supporting or
indicating that high levels of inflammation are at least
currently an indication of like aging, a big biomarker for aging
at this point. What have you seen about this?
Have you experienced this or have you talked to people about

(42:19):
this? I'm just curious, you know?
It is quite interesting actuallywith the inflammation story
because this is what I was learning 20 years ago and it was
very, very new, but now everybody's talking about it.
There's a lot of nuance that people don't necessarily
understand. So there is a term called
inflammation. So we know that ageing is

(42:42):
related to some inflammatory processes in the body.
That's true. We know that sustained.
So inflammation is really important.
When we have an injury or an issue, we knock ourselves and
actually what we need is for body to swell up, get red, get
hot, and everything's coming in and it's fine.

(43:02):
Yeah, exactly. So it's a really, again, like
also it's an important thing. Sustained levels of low grade
inflammation are linked to a lotof chronic diseases, in
particular are metabolic dysfunction.
So type 2 diabetes, cardiovascular disease, you
know, neurodegenerative disease,you name it.

(43:25):
The thing that most people don'tknow is that we don't actually
have any way of measuring low grade inflammation in your
average human. It is extremely hard to do.
In fact, it we can mainly only do it in animal models because
they're the very short lived bits of inflammation just aren't
detectable by most, most kind ofassays that we have.

(43:49):
And if you have really severe inflammation, it usually
indicates something else is going on that.
So if we can do a test, blood test for inflammation, there's
usually something else in the body that's causing that, an
infection, a cyst, something is going on.
If we have very small levels of inflammation that we can detect
with something called high sensitivity CRPC reactive

(44:12):
protein, then that can indicate an increased risk of apart
disease. And we know that, but there's
lots of other things that can cause that and is just quite an
interesting topic because peopleare talking about inflammation.
People feel like they're inflamed, but they've got
nothing to pace with with. And it's just, it's kind of

(44:35):
fascinating to me because this is such an interesting part of
my like kind of academic life before I started medicine.
And it's we don't really know very much about it.
We know it's important. We can't really measure it.
So it's impossible for you to know if you're inflamed at a low
grade level, you know, if you'vegot something massive going on,

(44:56):
of course you will. That will, we will see that in
blood tests. And I think all we can do is
support the conditions that we know are associated with lower
levels of inflammation. And often that is sort of eating
the right sort of diet to support our gut microbiome,
doing exercise. It's really important, but also
managing stress. That's one of the big potential

(45:18):
drivers of low grade inflammation.
So I'm going to keep coming backto stress because I think it's
just so important and it's the one thing that most people just
don't want to try and deal with.Yeah, I feel like at least in my
experience through all these years, several decades now, is
that people are more than willing to try a variety of
different interventions, particularly for their health

(45:38):
and well-being. But if you talk to someone like,
hey, you really need to lower your stimuli, the amount of
stimulus in your life that's causing you stress, It's almost
like, well, what am I supposed to do?
I mean, I have this busy life, Ihave this family and all these
things. Something that feels like there
can be control, but this weird resistance to it.

(45:59):
I mean, what do you think that is?
It's hard to say. And I think I have it myself to
be honest, because it's it's part of this busyness culture.
I think we are, we are conditioned to believe that our
worth is related to our output or our productivity or how many
views this podcast gets or how many views my little social

(46:19):
clips that gets. We are so conditioned to seek
that level of kind of external validation that we forget that
actually doesn't matter a job. And on our deathbed, we are not
going to be caring at all whether we did this or whether

(46:40):
we worked hard enough or whetherwe started work on time or, you
know, we're going to be thinking, you know, did I do the
best I could by my family? Did I find some people that I
loved in my life? Did I do the things that I
wanted to do? And I think it's extremely hard
when you're trying to balance a career, particularly if you've

(47:01):
got your own business or you're studying or, you know, you don't
really have that much money. You've got a lot of kind of
financial pressure on you. You've got this time of your
life when you feel I've got to make it now or never, but you're
also quite aware that your health is only going to get
worse. And I think something needs to

(47:21):
shift with the way that we all think about this.
And I agree with that in this because I, I'm just, you know,
so aware on a day-to-day basis, if you track what you do,
including other practices like exercise, meditation and screen
time, if you're feeling bad, I can almost guarantee it's

(47:44):
because you're looking at your phone too much.
If you before bed almost there to be, you're not getting out in
nature, you're not doing enough exercise and you're spending
absolutely no time in stillness or when or in any kind of method
to practice like, you know, a hobby or something.
And unfortunately, that's what most of us spend our time doing.

(48:07):
You know what's interesting, I feel that, you know, my
practice, these are huge cornerstones of my business,
gigantic and something I've worked incredibly hard on
throughout the last 25 years. And I practice and, and is a
huge talking point among my clients.
And I always say, listen, what we're doing with exercise, the

(48:28):
physical aspect, it's important,but it's just the price of
admission. And the deeper we go into these
other areas, mindfulness, boundaries, lower stress, this,
these, these are the things thatare going to really change your
life. And beyond the physical part,
obviously, but it's going to give you a much fuller, richer,
more relaxed life, honestly for that.

(48:52):
But let's not forget it does have impact on our physical
body. We know mindfulness meditation
decreases blood pressure. We know that it's 'cause some
effect in sort of silly listen essence.
So our aging, we think there's some something to do with
meditating and that there's all sorts of data showing us that.
I think, and I don't know if you've you've experienced this

(49:13):
with your plans. I think people need permission
to do things that feel nice for themselves.
It's so funny you mention that. I think people are hard on
themselves. If they feel like they're doing
less or taking time to support their kind of holistic
well-being. There's a guilt associated with
that and you have to, I've done this plenty with people and like

(49:36):
just telling them it's OK to focus on yourself and to take
time and just not be present with all this other stuff you
have going on. And I've actually been, I was
talking to my wife about this yesterday.
I was like, it's very important to be selfish.
I know this sounds like a, we'vebeen told this is very negative
to be selfish. I'm actually bullish against
that. That's very important to be

(49:57):
selfish so that you are actuallyavailable for other people in a
meaningful way for that because we often will take care of other
people. We're caretakers for other
people, especially family members, you know, children
stuff. But we neglect our own
well-being within that, which actually becomes a net negative
over time. Then the people who love and

(50:18):
care for you start saying that you can't actually take care of
them and help them because your health is deteriorating.
So it actually becomes a negative over time for that.
But it's very difficult to get people out of that, that thought
process, you know? I mean, I know that in, you
know, intrinsic and I think there's also this, this sort of

(50:41):
thing that we have in our mind that unless it's unpleasant in
the Sunway, it's not good for us.
You know, it's like actually zone 2 exercise is really good
for you, but it's that hard. Like compared to lack of
spinning glory, it's actually not that unpleasant.
It's OK, but it's really good for us.
But then we must resist doing itbecause it doesn't feel that
hard or, you know, lots of really delicious food is really

(51:02):
good for us, but we think, oh, can't be that good for you if
it's delicious. So, you know, I need to eat
some, you know, kale smoothie orsomething disgusting to feel
like I'm doing something healthy.
And I think with the same, we'rekind of quite masochistic.
I think we're kind of our lives.And then and it's to our debt
children. I, I'm forgotten the quotes.

(51:24):
I've read it a couple of days ago, but it was something like
in all the busyness, I sort of forgot to live or something like
that. And it's so poignant, isn't it?
We can spend all of your, all ofyour life just doing bits and
bobs and going for your To Do List.
And then it usually takes something to happen or somebody
to get sick or you'd get sick or, or a scare to kind of jolt

(51:45):
you out of that. And I would hope, I'd love it
for people to not get to that point before they started to
say, actually, do you know what?I will be selfish.
I will take just 10 minutes for myself today.
It doesn't have to be all day. It's just little portions of
time that you can give yourself during the day and it makes all

(52:06):
the difference. 100% I want to be cognizant of our time here,
your time. It's the audience.
We're in a very large time difference and Doctor
Merrifield's in. It's Friday night, please.
That's. Right.
And my Friday night will be beginning eventually.
But I want to talk a topic that also gets discussed with my
clients quite a bit and just general conversation and larger

(52:27):
health and well-being filled in particular testosterone and
estrogen. But let's start from the
estrogen point of view in terms of hormone replacement therapy
and menopause and where are we at with the data in terms of or
more pro HRT or are we in might be more the past idea of this?

(52:49):
I would say we're probably moving towards pro HRTI think
it's a bit of a slow and process, partially because the
trials haven't have been done onsome of the older preparations
of HRT. But when I we've got better HRT
around and certainly some of thebig names in in menopause have
really commenced me like Louise Newson.

(53:10):
I don't know if you know how there, but you know, I'm really
thoroughly convinced and will betaking HRT myself unless it
happened, sail through the menopause without noticing that
it happened. So I think overwhelmingly pro
and I think what's happening at the moment is there's a lot of

(53:30):
more awareness of all of the negative effects of menopause
that aren't just hot flushes. That would be the only thing
that you'd ever talk about 10, 15 years ago.
Whereas now I think people are realizing the really quite
detrimental effect on mental health that's that women
experience as their estrogen levels kind of fluctuate,

(53:50):
particularly around perimenopause.
Now, actually postmenopausal women are less likely to be
depressed. So it's not all about estrogen
either being there or not, but Ithink they're certainly around
that transition. That kind of fluctuation can
really play havoc with memory, our kind of well-being and
causes a lot of vulnerability inpeople who sort of get into a

(54:14):
stage of life where they want tobe, you know, finally enjoying
the fruits of their labours and and kind of enjoying life a bit
more. So I'm pretty pro it personally.
And I think that the new preparations are really very
safe and there's a lot of ways to take it that's you can kind
of titrate your symptoms and andget a lot of relief.

(54:35):
So. I'm seeing that too, like more
of those consensus and academic and medical consensus and pro
HRT. What about for testosterone?
I haven't heard as much about this for men at at different
ages. I think it's a difficult one
because so testosterone testing is an interesting one actually,

(54:58):
because it's, I think what's thestatistic?
It's something like one in four men over 40 have got low
testosterone, one in five, something like that.
So quite a high percentage of people.
But we know that testosterone isactually one of the hormones
that's very sensitive to your lifestyle.
So if you're not sleeping, if you're very stressed, if you're
not eating well, if you're not moving, that will all contribute

(55:22):
to low testosterone. So those are the first things
that you can sort of work on to improve testosterone levels.
I would say that in people who have genuinely low testosterone
because of a central problem, problem with the brain producing
it or or have the sort of properendocrine reasons what they
don't have it, testosterone replacement can be absolutely

(55:44):
knife changing. And I've sort of seen that a lot
at particularly sexual health kind of conferences where they
where we've had people speaking about their experience with it.
And it's slightly an under recognised thing because we
don't always test for it. It's it's something that men are

(56:04):
often a little bit embarrassed about talking to doctors about
if they don't have a low libido,which is obviously one of the
main, main kind of symptoms of alow testosterone.
So it's often something that people don't mention.
So they don't necessarily seek treatment as much as they could
and should, but it certainly improves the quality of life in

(56:25):
men who need it. Awesome.
I think we could spend literallyhours going over all this stuff.
I always have sons of questions about stuff like this, but I am
so grateful that you've given mesome of your time.
And I know that my colleagues, students at various
universities, and clients as well are going to greatly

(56:46):
appreciate this. Thank you so much, Doctor Mary,
for your time. Seriously, this was a wonderful
deal. Thank you, I really appreciate
you having me on and it was a real pleasure to speak to you.
Most definitely. And you have to get to your
Friday night. You know, the kids are bedtime.
You got to enjoy yourself. I know.
We know what that's like. Yeah, of course I got to I

(57:08):
beauty sleeping got. To get your beauty sleeping,
yeah. Thank you so much, Jack.
Really appreciate it. Enjoy the rest of your day.
Yeah. You too.
I appreciate you. Thanks a lot.
Thanks so much. Bye bye.

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43. Endocrine System Basics and Care w/ Dr. Claire Merrifield

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