Kind: captions
Language: en
if you assign people a diet for a year
and you say you're going to have a high
carb diet and you're going to have a
high fat diet and i watch you for a year
the weight change is the same
and you can lose weight on either of the
diets depending on how well you stuck to
the calorie counts not the carb counts
herman poncer phd welcome to the show
yeah glad to be here
dude i'm really excited your book burn
seems uh
designed to challenge what people think
they know about nutrition
and
i have
the first sort of controversy of my
career back at quest was around a
calorie is not a calorie
and we put out the show called the
calorie myth and people went ballistic
and i'm talking you can't imagine how
surprised that was i was like that's
just like the 101 that's the
non-controversial one and people went
crazy anyway i formulate my hypothesis
around calories and that a calorie isn't
just a calorie and that there's hormonal
signaling going on and that the body is
basically far more complex than just
calories and calories out and but
recognizing that that's a very
controversial stance
um
what in so you've studied the hards uh
and we can get into that but i'm
actually far more curious about why a
calorie is just a calorie and why if we
want to burn fat
that we have to think about a different
mechanism than that hormonal signaling
then the insulin response things that i
thought we could take for granted
yeah so
i don't think anybody who
views you know who works in the world of
measuring calories like i do uh thinks
that all calories are equal in the way
that that sometimes it's implied so
there's this you know there's there's
kind of straw meaning that goes on on
both sides of this argument and one
version of it is that um
when i say something like well
to gain weight or lose weight it's all
about the calories you consume versus
the calories you burn off
that gets framed as oh you're saying
that the type of food doesn't matter
right or that if all foods are the same
or like 100 calories of potato chips is
the same as 100 calories of broccoli and
i don't think anybody who works in
physiology really thinks that in terms
of
the effect it has on your body
um those hundred calories will in the
end have the same effect on your weight
if that's if if that's all you ate
right
but um you know the fiber in the
broccoli and for that matter that the
flavorings and the potato chips are
going to have different effects on the
way that they affect your brain and on
hunger it's a tidy signaling so
i don't think um you know the the
all-calories or equal thing i think can
gets caricatured a bit into thinking
that that's all we care about um i don't
think that's all we care about
on the other side of it i think you know
when people say well if you're saying
that all calories aren't equal then
you're basically agreeing with the idea
that it's all carbs and insulin
right and you know if we understand that
insulin is this really important hormone
that has effects all over the body and
insulin is is really important for
getting glucose into your fat cells um
you know turning glucose into fat then
well then we must be in agreement that
insulin really is important and it's all
about insulin and and the fat cell right
and well hold on a second now
insulin and its effects are of course
huge and systemic and all throughout the
body but that's not the only thing
that's going on when you eat there's
tons of signaling that's happening
there's hunger satiety signaling that's
happening in the brain
some of that's mediated by insulin but
actually a lot of it's not
you could have insulin can have its job
nobody just disagrees with this about
getting fuel out of your blood and into
your fat cells and packing your fat
cells full of fat insulin can have that
job and still not be driving the bus
when it comes to weight gain and weight
loss right so i think we have to kind of
unpack here and sort of agree to
how we're going to think about this to
have a really fruitful conversation
yeah now i'm with you on that so the
place that i want to start is to build
up the two different arguments that are
going head to head and then why they
matter and then we'll get in there and
begin to tease this out and i'm gonna
push back on things based on
what i have
come to believe
so here's how i see the two arguments
there's argument number one is hey the
reason that we have the obesity epidemic
here in the west is because people are
over eating calories and the second law
of thermodynamics is such that energy
cannot just disappear it's you know
going to stay so sun hits the plant
animal eats the plant animal grows we
kill animal we eat it or we eat the
plant but we're basically just turning
sunlight into
cells for our body and if you intake too
much of that energy in the form of
kilocalories as you very accurately
describe in the book if you eat too many
of those then
no matter what you are going to put on
weight and there is this
extraordinary mechanism in the body
where it's really going to make sure
that whether you land a couch all day or
whether you're running marathons all day
your energy output is basically the same
which seems impossible to believe but
you have some incredible data around
that and so we'll get into the haza so
that's
argument number one it goes head-to-head
with this second argument which is come
on man like what if i'm eating a twinkie
that is so different in terms of my
bodily response than if i'm eating
broccoli and so you can't just say that
a calorie is a calorie i'm not going to
get morbidly obese by overeating
broccoli i'm going to get morbidly obese
because there's all these other things
like sugar being sort of the biggest
villain that are in these foods and it's
really the sugar that's the problem even
more than the overeating and they will
grant that sugar probably compels you to
eat more than you would otherwise but
really sugar in and of itself is a
problem and so it's a calorie is not
really just a calorie so we get these
things that come colliding in your book
and i think now starting with the the
thing that you set out to research with
the hadza and that whole framing is the
right place to start like i want to get
into
why did you want to study energy
expenditure and why did you think they
were the right people to study
yeah well so i wanted to study energy
expenditure because that's where the
rubber hits the road in evolutionary
biology and i'm an evolutionary
biologist that studies humans
um and you know life is a game of
turning energy into kids
and so evolution is nice evolution is
all about that uh you know strategies
behavioral strategies physiological
strategies that do that better are
favored by natural selection
and so you know that that's really
energy is really where it's at when
you're thinking about the kind of the
currency of evolution and the currency
of biology um humans
evolved as hunter-gatherers
uh the human lineage has been hunting
and gathering for over two million years
our species only shows up about 300 000
years ago so we're hunting and gathering
species from hunting and gathering stock
and you know in the same way that if i
want to understand
a bear or a dolphin or any species of
animal i want to understand it in its
ecological context and the context in
which it evolved i don't want to study
it in a lab necessarily i don't want to
study it in a zoo i want to study it
where it evolved
for us that lifestyle is hunting and
gathering so i want to find communities
that are still doing it
and they allow us to ask the question
how does your body function
in its sort of ecological
nor you know natural setting
uh and so there aren't many populations
that do that anymore so one of them is
the hunt the haza community in northern
tanzania and we went to measure energy
expenditure there and we thought that we
would find because they're really
physically active as you can imagine
hunting and gathering get men get 19 000
steps a day when we get 13 000 steps a
day
we thought that they would have sky-high
energy expenditures
and in fact they don't uh they have the
same daily energy expenditure
as your typical american your typical
european your typical industrialized uh
relatively sedentary human so that was
the first hint that uh this isn't
working the way that that out that i was
taught you know that uh in this sort of
simple version of how metabolism is
supposed to work so
that you get this confounding mystery
you guys are using would we call it the
the gold standard of caloric uh
expenditure
a brief snapshot of what that is i think
would help people sure so you drink some
it's called the double labeled water
technique you drink some water where the
you know it waters h2o you drink some of
the water you drink some water where
some of the h's are deuterium and some
of the o's are an isotope a different
form of oxygen and we can use those as
tracers
and the hydrogen isotope tracer becomes
a tracer of water throughput through
your body
the oxygen
isotope becomes a tracer of
of both water and the co2 that you
produce when you burn calories
and so if we if we subtract the
deuterium signal from the oxygen signal
the only thing that's left is the co2
you produce every day so it's a precise
measure of carbon dioxide produced over
the course and we do these experiments
over about seven to ten days
so it's a pretty good you know snapshot
of your life a seven to ten day long
snapshot of your life and how much
carbon dioxide you produce and you can
only produce co2 burning calories and
you can't you know so that it's a really
good signal of calorie burn um and it's
the gold standard for anybody outside of
a laboratory
and when we talk about calorie burn you
mentioned in the book that you don't
think most people understand that you're
exhaling most of the calories that you
burn versus other things that we
probably think about it as you know
using your muscles or whatever but it's
uh it's actually just part of the the
metabolic rate of all of your cells as
you manifested by exhaling the
carbon dioxide and we start getting this
data back
and we're saying wait a second they're
not
using more energy what's your first
leap
as to why how that could be possible it
doesn't seem possible well no the so the
first reaction was we
i
i don't know what your language rules
are what would that be screwed up
uh
the first expect i mean that that's the
first a good scientist always assumes
that they screwed up when you get funny
results
uh and you know i i think we were pretty
careful about that so the first thing we
did is we we actually used a whole a
second way of measuring energy
expenditure with with calibrated heart
rate monitors
and got the same answer so the hodzo we
knew the hadza data were real um and
then we thought well maybe it's just the
hodges so then we've now looked at this
in the and
two other populations of
sort of foragers in south america very
carefully and looked at other data from
other groups as well but but
my lab is specifically involved in two
other populations of work
we looked at this in other species like
a like a monkey in the zoo
has the same energy expenditure as the
monkey and a monkey in the wild
uh you know so it's the same everywhere
and across species so this is a really
fundamentally evolved system in humans
and other species to keep your energy
expenditure in in check and that makes
really good sense because you don't want
to have you know your energy expenditure
on the one hand it's good for you
because all that all that's all that
cellular work that's doing all the stuff
that you're evolved to do you want to do
that you know you want to have an immune
system that's functioning and
and uh
you know a nervous system that's going
you want to be physically active so all
that cellular expenditure is good
but if you go over of course
right day after day for a long time and
you
if you overspend basically you go
bankrupt and what does that mean well
when you overspend calories chronically
you die uh so no kidding no wonder that
the body doesn't want to do that
now one of the things that i found in
the book that was really like okay i see
how we start to weave these threads
together
is that when you look at all the genes
you said there's some more than a
thousand genes that have to do with
whether or not you'll end up obese yeah
and you said the vast majority of them
have to do with the brain yeah and that
was like
okay okay so uh
yeah so why does that happen
when we the one of the first things that
happened um
after we published this hazard data and
i think people found it really
surprising um
and you know
gary taubes reached out to me actually
and said hey you know that's really
interesting data and he was super nice i
want to just be really clear he was he
was really nice and collegial and he
said this is really interesting and you
should really think about this in terms
of not calories don't worry about that
you should be thinking about this in
terms of carbohydrate because you know
the reason that they're able to stay at
this healthy weight isn't because of
energy expenditure
um or at calories burned it's because
you know of of eating this paleo diet
kind of hunter gathered a diet that's
low in carbohydrate
and i thought that's a really
interesting idea
the problem is
the hots eat tons of carbohydrates in
fact they eat more carbohydrates than
the standard american diet and less fat
and they get it in terms of honey and
tubers those are the ones you mentioned
in the book and tubers and and berries
uh yeah
to 50 of their calories come from uh
from meat and fat from animals and the
rest is uh
is you know
um it is plants and honey so um when you
do the calorie you break down the
calories on that you know you've got
protein and fats from the animals of
course but then you've got um about yeah
60 percent of their calories even more
uh from from carbs
okay so very interesting so we're we've
got all these hypotheses that are
starting that try to make sense of
what's going on okay they're not making
sense of it um so as you're there you're
with the hazza you know that okay
they're not expending more energy i know
that obesity the genes for that tend to
be clustered in the brain meaning that
there there's a control mechanism going
on in the brain that seems to have
something to do with whether or not you
end up getting obese yeah talk to me
about the brain and the hypothalamus as
the control mechanism so i i totally
understand what you're saying in terms
of why it's important to stay in that
band but how
do we stay in that band yeah so um
so your hypothalamus is at the center
of a
many tentacled
system
that's got it's it's got its uh feelers
out
into your bloodstream your nervous
system
um via your bloodstream into your
hormonal endocrine system
it it also it tracks your your energy
levels basically uh
and so it can it can sense when
nutrients come in
and it can sense how much comes in it
has uh you know it communicates with
your brain stem to talk to know how much
your stomach is stretching when you get
a big meal for example
um it can sense insulin it can sense uh
you know protein intake all the stuff so
it knows the nutrients that are coming
in it's also hooked up uh
in
to your reward system basically in your
brain that is the
you know the all the happy feelings you
get when you eat food that's delicious
and leptin which is a hormone that gets
released when you are when your fat
cells are getting packed they they
really they produce leptin so you're
able to to sense with your hypothalamus
how energy is coming in
um and your hypothalamus is also in
charge of your thyroid so the
hypothyroid the hypothalamus it
communicates to the thyroid to to to
turn it up or down
and thyroid hormone
what does the thyroid do your thyroid is
like the master um the master control
for your metabolic rate
so more thyroid hormone in general makes
you burn calories faster less hype less
thyroid hormone makes you burn calories
slower um if anybody out there listening
has had thyroid issues you know this or
if you're hyperthyroid you tend to sort
of you're too warm and you're your
body's burning calories too fast if
you're hypothyroid
low thyroid you're burning calories too
slowly
okay so even
sorry before you go on because this i i
am always confused by
um
i have my hypothalamus dipping into my
bloodstream stretch responder like all
of the things that it's checking and
i don't think it checks calories right
well what are you so how do we know what
how much you're eating right so there's
two ways you know about calories
uh you are checking nutrients in and
you're checking uh your your basically
your fat stores by checking leptin
levels uh and you're so
you don't have so so let's
unpack that a second because that's
often that's often a critique well
there's no calorie sensor in the brain
okay
actually there is because you you have
tons of data coming into your brain
about the nutrients in
and you also have uh information
entering into your brain about when
you're a negative calorie deficit
so when you're when you're burning more
calories and you're eating your brain
knows both of those quite well
and one way that you can tell
that the brain is able to sense calories
very very precisely actually is this
this is work that rudy libel did in the
90s but they've done it since in other
studies if you increase somebody's
energy intake you make them overeat
not crazy amounts you can't do this
forever but about 10 more than they were
at baseline their energy expenditure
will go up 10
if you
make them eat about 10 less their energy
expenditure goes to 10 percent less 20
less you can even track that
and so your hypothalamus is at a system
that is matching energy intake and
expenditure
so precisely that you know even in
america where the typical
the average american gains a couple
pounds a year
that amount of weight gain is a tiny
tiny fraction
of the food that's brought in right um
and so the
you know to within like less than a
tenth of a percent
right you are matching it perfectly 99.9
perfect match of energy and energy out
and so
there's no way that that's happening
without some regulation about
that sensing calories and matching it
because nobody eats the perfect amount
of calories every day right
or even every week and so you're you're
actually doing this level matching very
well so this idea that you can't there's
no calorie measure in the brain
i take the point that there's no you
know in the same way that you have like
a barrel or expensive uh
sensor to do stretch in the you know to
do blood pressure you have a temperature
sensor we know the neurons that do that
okay
true but we have lots of nutrient
sensors and we have lots of other
indicators that tell your body very
nicely about how many calories are
coming in versus going out so that's
kind of a red herring i think
so what i'm trying to get to is
why we have really smart people that are
like two ships passing in the night on
this issue and i have a hypothesis that
literally i'm formulating in real time
here um that part of the issue is
that you you've got the hypothalamus
checking all these different things and
then it's talking to the um
the thyroid and it's dialing up or down
your metabolic rate
and so you have a reaction
to
the things that you're in taking that
will not be universal so it will be
unique to that individual and i'm sure
it's a whole host of things
that feed into that so i will give you
an anecdote that will explain why for me
this has seemed until reading your book
self-evident that it isn't just a
calories a calories a calorie right
because
there is a
relativistic change where i'll react one
way but my wife will react to different
so for instance
if she if and you're gonna think i'm
kidding and you go to great lengths to
explain in the book that people do not
understand they can't track their own
calories so
but if my wife and i were to eat
calorie for calorie
yeah the next day she will wake up and
again i'm not kidding you can actually
ring the sweat out of her side of the
bed
whereas i will just be fatter
and it is so irritating because my wife
who's like half my size can match me by
calorie and what happens is clearly her
i would assume her metabolic rate is
turning up which is making her hot and
so she is
sweating through the sheets yeah in in
response to the same food that does not
make me sweat but i am noticeably either
retaining water or actually having put
on fat whatever the the thing is i look
fatter
yeah and so that
that difference makes you go hold on
there's something going on here other
than just a calories and calories a
calorie
oh totally so so the problem is that
when we begin to say oh that must have
been something in the food that you ate
rather than oh it's something in your
individual
response to that extra energy and what i
would say is my hypothesis would be
your your wife's regulation of calorie
intake and expenditure
it was better matched and she was able
to crank up her metabolic rate and burn
those extra calories off that was her
evolved response from her hypothalamic
system
yours was different yours did not
increase your thyroid hormone in the
same way and maybe it did become extra
calories uh maybe extra calories still
on you as as weight
and gosh you know if that were true then
that would mean that the genes
responsible the gene variants
responsible for obesity
would be
where they'd be in the brain and that's
exactly where we find them and so
i i hear that anecdote and you know i
think yeah that that actually mates with
what what that's that matches the data
that we see
the problem with
the
sort of carb blaming or whatever blaming
that you want to do is rather than
thinking about the calories that came in
and how your body's responded to it
rather than thinking about oh it was one
special nutrient it was carbohydrate and
it was the carbohydrate that made my
insulin go up and my insulin took my the
the uh the blood sugar and put it into
my fat cells
and it didn't in her you know for some
reason
then
the the
that's a reasonable hypothesis by the
way and i don't want to make it sound
like it's we could just dismiss it it's
a really nice hypothesis
it has generated lots of good science
it just turns out not to be very true
it doesn't hold the data very well and
here's why if that were true then the
pathways that vary between you and your
wife or that at a population level vary
between people who have higher bmi and
who don't
we should find those pathways and the
alleles that are the genes that are
that are vary that make the difference
active in those pathways and we don't we
don't see them active in the pancreas or
the fat cell or the liver we've people
have looked and they're not there
they're active in the brain
secondly um
if we do controlled feeding studies then
we ought to see
high carb versus high fat diets have
that kind of response
regardless of calorie counts we should
have people who are on high fat diets
lose weight or maintain people on high
on high carb diets gain weight
and that you know matched calories for
calorie because the argument here is
it's not calories it's carbs and when
you do that controlled study it doesn't
work out that way um it really does come
down to the the calories are what
determines the weight change or
maintenance not the carb
level so that's work that like for
example kevin hall has done but not just
him other people have done it too
um and it works in the lab and it works
in the real world settings where
if you assign people a diet for a year
and you say you're gonna have a high
carb diet and you're gonna have a high
fat diet and i watch you for a year
the weight change is the same
and you can lose weight on either of the
diets depending on how well you stuck to
the calorie counts not the carb counts
and this is the most exciting one
i don't know if you've been paying
attention to the the work coming out
with uh semi-glutide so summa glutide is
it's called a glp-1 react
receptor agonist and basically this is a
hormone that gets made
by this by by your digestive system
and it triggers the
it's a it's a signal
to the pancreas to make insulin because
it tell you you create glp-1 when you uh
when you eat the stomach and the
digestive system uh
sense that food that comes in and you
make this hormone glp1
and like you'd expect it tells the
pancreas to make insulin because you
just ate so you better get ready to deal
with the nutrients and it tells your
brain that you just ate as well
um
and so they can make a mimic for this
hormone
well this mimic for this hormone does
two things one it increases your insulin
and it tells your brain
it tells your brain that you you ate it
you didn't really but it tells your
brain that you ate
this is a perfect perfect test
of the carbohydrate insulin model
because if it's only insulin that
matters then you should gain weight
because your insulin's gone up and if
it's only signaling about hunger and
satiety in your brain of the
hypothalamus system that matters it
should make you lose weight because you
told your brain you ate
and it is the most effective weight loss
therapy
since bariatric surgery
people lose twenty percent weight on
semiglutid uh
so just because they don't have a hunger
mechanism because the brain is getting
told uv they stop eating
um and their insulin levels by the way
are higher um
at least initially the good news is if
you lose a lot of weight which you do
then your blood glucose levels go down
and your insulin levels go down so that
all you know all the good things happen
anyway it doesn't like your insulin
levels stay high forever and high
insulin probably isn't good for anybody
regardless of whether or not the cim the
carbohydrate insulin model is right or
not um so it gets all those things down
and it's that's good but the initial
input is actually increase insulin not
decrease we start getting into complex
things that i think are what muddy these
waters so for instance bodybuilders
routinely inject insulin as a way to
grow more muscle
because insulin gives your body the
signal to grow and so you start getting
into nutrition partitioning and telling
instructing the body what to do with the
nutrients yeah and if it's true that
insulin tells your body to grow which is
why bodybuilders inject it
and eating a high carbohydrate diet
spikes your insulin then it's obviously
it can't grow without
taking more of those nutrients to your
whole point about energy so now i've
given my body a food that signals to
retain this energy versus giving my body
a food that either just doesn't have
that signal or signals to dial up the
burn rate or whatever it it comes down
to calories in a hyper relativistic way
in that some people will respond to that
excess of calories differently than
somebody else so my wife her metabolic
rate seems to go up whereas mine doesn't
go up certainly not as effectively it
doesn't match as well to use the words
he used before and so it creates
potentially
it's not even it is an illusion in terms
of it isn't that i broke the laws of
physics but it's also real that i put on
fat and she doesn't and so it's sort of
of little
um consolation to somebody that is like
no no no you the laws of physics are
there it's like well i'm getting fat and
this person is not well yeah i think
that's i think the response is
individualistic and i think also that
the diet you know the hedonistic
response do i keep on plowing through
this plate of food or am i done
that's also going to be very
individualistic and people who go on low
carb and say this is amazing i've i can
eat all the calories i want and i never
get
i never get big in fact i've lost weight
you know
that's great and i'm so happy for them
other people say i want vegetarian and i
eat all the carbs i want as whole
vegetables and i you know and i never
count calories i lose weight that's
great too and the reason it's working is
that
you know two two sides of the coin here
one is that you're actually just
stopping earlier you feel full you feel
great and that's the that's the holy
grail isn't it that you have a diet
where you you just feel like you ate
exactly enough and you feel really good
um and that can happen on a range of
diets for different people are going to
find it with diets that work and also i
mean i think you're probably right that
the response to overeating the the way
that the body manages that calorie
excess if you do go over
is going to vary by people as well
that would be really fantastic to be
able to lock down and test and see i'd
love to see that we haven't we don't
know that yet but i think it's it's
plausible that's that variability
happens too
in every case we're still talking about
a sort of brain-centered system
rather than you know a pancreas
adipocyte centered system and so that's
if people
are kind of on twitter watching the
arguments between the carb folks and the
energy folks that's
you know if what i just said sounds
reasonable to you
then that's not actually the argument
the argument is is this more in the
weeds is it
fat cells than pancreas or is it brain
cells and sensing
so as you look at all this data um how
do you you're obviously in shape how do
you think about lifestyle like what's
the right way to go about it
what do like do we have the occasional
twinkie how do how do you approach it
i uh
and maybe this is just the way i'm wired
i just wish we would take the you know
turn the temperature down on this stuff
a little bit
the emotional temperature the emotional
temperature on this stuff down uh i
one of the great gifts of my career
being an anthropologist is
that i am it is my job to keep
eyes open and look across cultures and
look across human experience and see
that diversity and understand all of it
is pretty normal
right that the the
uh
the
universe of normal for humans is pretty
darn broad
and so
i get nervous and i just am skeptical
about anybody who's trying to sell you a
very narrow view of what normal should
be or what healthy should be
and it has to be this and it can't have
any of these
and you know i'm not sure about that i
think
try to stay as active as you can more
active the better
uh unless you have over training
syndrome then you've done too much but
none of it probably you're not there
unless you're like an olympic level
athlete
so we should all be exercising more uh i
think if we can do it outside all the
better um
i think you know
some people are going to find
diet wise that a really
strict diet works great for them because
that works for the way that they're
wired and their you define strict
because i know people are going to want
to hear what what basically
i just mean
that has a diet that has a lot of
brightline rules i don't eat any of this
you know i look at my list of foods that
americans eat and i cross off
you know half or more of them and i just
never ever eat them ever
um i think and if you had to pick uh
like a thing to judge them by would it
be
whole food is always best and so don't
eat anything processed or do you have
like what are your brightline rules
or what brightline rules could we
extract from the hadza like i'm not sure
the yeah but for somebody who really
wants optimal health
okay yeah i think the best thing to do
would be to avoid ultra-processed foods
yeah because they're
palatable or is there something else
that makes them problematic
there's a few things one is they are
hyperpalatable so they they screw up
that hedonic response you you overeat
because you don't ever feel full
and you always feel your brain is always
excited about it
they are
typically in the processing they are
any fiber is taken away
they're usually low protein so there are
your two you know there's a there's more
than two but those are two good signals
to your brain that you've eaten enough
is that you have enough bulk and that
you have protein
um and so you take those two signals
away
then you're going to over consume you're
going to go over consume carbs or fats
or both because that's all it's like
that's all that's going to be left in
this thing is carbs and fats
um they're they ultra processed foods
commonly have lots of added sugars which
are no good lots of added oils are no
good so you know if you can avoid those
pre-packaged foods that are stuffed full
of that stuff and and all the good stuff
the protein and fiber has been ripped
out
if you can avoid that and and try to
look for whole foods and stuff that's
you know minimally processed and not
destroyed in that way
i think
a lot you know i suspect that would
solve a lot of problems
i know that over half of the food
half the calories that americans consume
these days
over half of it is ultra processed
calories uh the number one
single source of calories in the
american diet is added sugar
followed closely by added oils
so you know uh
we got to stop doing that i think that's
what i would focus on
so
you in the book you obviously
acknowledge like there's nuance here and
i'm not saying that this is good bad or
indifferent is that an area that you
have studied planned to study in terms
of like why is oil bad
why is sugar bad like if it isn't the
sort of insulin sugar answer to why
people get fat
why do you worry about sugar
oh because i think that
hyperpalatable foods ultra processed
foods
um they screw up the energy matching
signaling that your hypothalamus does
they are too
delicious so you're pushed to overeat
them they are devoid of the signaling
molecules that would typically tell you
that you're full and so
you know when when hunger and satiety
have to be in perfect balance like this
and you just do that
well now you're in trouble right and i
think that's what i think is so
beautiful about like kevin hall's ultra
process food over feeding studies i
think they show that really nicely
so people who aren't over consuming and
aren't overweight
um
then i don't think you're going to have
as much of a problem although i'm i am
i'm walking i'm tiptoeing into stuff i
don't know as well so i'll be careful
but um i don't see the issue now you're
so
there's sort of a
i don't i want to make sure we're not
talking past each other i'm not arguing
that uh that just pure white refined
sugar is a great idea or it doesn't
matter or anything like that no you're
talking about trying to figure out this
vaccine
is what is going on like why is refined
white sugar problematic you've looked at
so much more data than i have if you
have a hypothesis around
why that's so i get the hyperpalatable
part and maybe that's it but i'm just
curious if there's anything other than
the overeating or no it's problem is
entirely it's just going to make you
overeat and i'm asking if somebody who
wants to be able to eat ice cream
yeah um i eat ice cream um so yeah i
think i think it's okay
look
sugar
is a fructose molecule and a glucose
molecules molecules stuck together
and when it gets into your blood that's
what it is and it's the same as there's
the same fructose and glucose molecules
that your body is going to break down
and use that way
from other carbohydrates so
you know table sugar and a potato and a
slice of bread and uh
you know a jar of honey
are all going to end up being the same
molecules in your blood
that that's just how that's how
digestion works and that's that's
reality
now
you know if if they're if you have white
refined sugar without any fiber to sort
of help slow down the digestion of it
and to signal like you're full then yeah
okay by itself that's a problem but but
i think it's not because
the glucose in your blood knows it came
from like refined sugar you know what
i'm saying i don't think there's any
memory that oh i came from something bad
so now i'm going to be worse than i
would be if i came from a nice a good
source right
so i do think it comes down to
matching your energy needs what you eat
and i don't think i think villainizing
particular kinds of of nutrients doesn't
help i don't know if that answers your
question no it does it's you know this
is uh
such a fascinating topic to me because i
start thinking about it in terms of okay
what's going on i step back and i look
at the american population and i say
even from the time i was a kid
it like so my family um i grew up in a
morbidly obese family and i remember
thinking about it as a kid like my
family's fat yo and like other families
are not
and now it's like my family is
completely normal like it is so common
and that's in like you know i'm only 45
so it's like not in exactly you know
hundreds of years so in that amount of
time it's become like so widespread so
you start asking okay what's going on
here yeah um over consumption like i'm
perfectly happy with the idea that
look ultimately this is a caloric
imbalance for that individual person
and but i think that just as you've been
very even-handed about that there are
also secondary consequences that beg
questions but the reason that i'm
i'm not yet full and look i fully
acknowledge this is largely ignorance
but i'm not fully convinced yet that
there isn't something going on with
carbohydrates because i think about
things like okay
if
insulin is
damaging cells
and there are
certain things that like
if
i eat a sugar a white refined sugar this
would be my hypothesis on why white
refined sugar for instance is worse than
honey that there's something in honey
that's slowing its absorption or
something so that even though once it
hits my bloodstream it's the same
but
if a white refined sugar doesn't have
any of those things around it to slow
its absorption
it gets into my bloodstream now things
like my muscles uptaking that sugar or
my liver having stores that it can fill
with that if i'm not exercising not
depleting that and i'm eating foods that
are
that get into my bloodstream faster so
they overwhelm the the non-insulin
response systems of my body and so my
muscles can't uptake it fast enough and
now there's oh way too much insulin
pumping through my system that's
beginning to damage my cells then i
start going okay well there's a logical
through line again the data may show
that this just isn't true but i can see
a logical through line to how there's
other things at play here that can
adjust a caloric deficit or not right so
the way that you would test that is is
you would assign people to different
diets and you would say you're going to
eat a low glycemic index diet high fat
and you're going to eat a high glycemic
index diet high carb
and we'll and we'll check back with you
in a year
and this has been done a few times
and
the result is consistent
people who stick to the diet
whether it's not as high glycemic index
or not if you stick to the diet you lose
weight and
everything gets better your
hba1c gets better your
your blood glucose levels get better
insulin resistance gets better people
can be you know the the diet fit study
that you probably have heard about
people on the high carb low fat and on
the high fat low carb diets had similar
percentages of people who reversed their
type 2 diabetes
reverse is a is a tricky thing but they
didn't they no longer needed medication
they were they were able to maintain
sugar in a safe way in their blood
um
weight loss was the same uh and so
when you lose weight
this is why i tend to focus on weight
and first and the the secondary stuff
second
when you if you're overweight and you
lose the weight
those measures all get better no matter
what so if you eat the twinkie diet but
lose weight you're you're still going to
be better off yeah that's right and you
probably still shouldn't eat the twinkie
diet i'm not recommending that but
you'll be better off eating the twinkie
diet and losing the weight
and eating some other diet and they've
done have they done something like that
with diabetics like so their weight is
coming down would they be able to better
manage their blood sugar even though
they're eating these high sugary foods
as long as they're in a caloric deficit
okay so doc if you if your body tips
over into this pathological state where
you're no longer responding to insulin
correctly
then i think that's a different
situation and people on high fat and
high carb diets who are sort of
pre-diabetic
have equally good outcomes that's the
diet fit series up response and that's
the danziger at all 2005 study that did
atkins ornish weight watcher they did
all five diets i think
so there are these diet uh there are
those if you are already in that
pathological state where your cells
aren't work you know your insulin
response is is pathological
well then i i think that's a different
game and i'm not gonna i you know i'm
not a diabetic i'm not a diabetes doctor
and i'm not going to
tell people what to do to keep i know
that if you keep on a really low carb
diet in that state you can do better
but that's talking to somebody who's
already has a sort of broken response
and i hesitate to take that as
particularly instructive about what
happens to people who have normal
response
so to me that's super intriguing and
when i see in a disease state it
responds well to this thing my natural
inclination is well then that's probably
the thing that led you to the disease
state
but the data may not be there to back up
that layman's hypothesis so i'm
perfectly open to that
let me ask you what would be your
fantasy test to run if you could lock
people in a room and they only ate what
you gave them like what what is the the
one question were you like if we could
answer this we'd really know about
health
oh i know how well
okay about dietary health
then that's easy you do this study that
um that kevin hall would love to do and
so maybe if somebody's listening they
want to fund kevin hall for this he's
already set up to do it rather than
doing you know month long or two month
long crossover studies you would do it
for a year and you would have somebody
in a you know basically in a hotel room
uh
and you would make them
you'd make sure that they ate exactly
what you said they were going to eat and
you would do biomarkers the whole time
to ensure that they were on track
and it's a very simple test
right
if if the calorie version of this is
right then it won't matter if they're in
the high carb arm or the high fat arm
their weight gain and weight loss will
be entirely due to
caloric bene you know
the number of calories you're eating
um
and if you put them on a negative
calorie balance and they lose weight
everybody benefits regardless of you
know from the weight loss regardless of
how they got there
the data that i'm aware of for dietary
studies that already in my mind say that
that's going to be the outcome but
we haven't done the lock them down yet
so let's lock them down and do it
and so the flip side is
if i'm wrong
and calories don't matter and it's all
about carbohydrates then it should then
if i have a high carb diet and a low and
a high
high carb and a high fat diet
the high fat diet that people should be
doing fantastic in losing weight even
though they're matched calorie for
calorie
right
and
that's the prediction of of that
carbohydrate-based view of the world and
we've done kevin hall's done the short
version of that it's not short i mean
it's still a long time to do a two-month
crossovers or one-month crossovers um
but
you know we've done the long version of
that where like which is diet fish which
is i give you a high carb diet and
you're assigned to that group randomly
and i give you a high fat diet and
you're assigned to that group randomly
and we see what happens in a year
um
and
so far the data support the energy view
but but yeah i mean if the the dream
experiment
is
is the lockdown study for a year
man this stuff is so intriguing i really
liked your book dude i took so many
notes it was freakish uh it was
absolutely fantastic thank you so much
for coming on the show where can people
connect with you get the book all that
good stuff uh yeah thanks you can get
the book anywhere you buy books so if
you're checking out your local local
book seller that's fantastic go to the
independent sellers
if you can't find it there amazon's got
it
and if you want to know what i'm doing
i'm on twitter at hermanponzer and if
you want to know what my labs do and you
can find us at duke um
yeah our podcasts and and shows and and
whatever else we we get invited to come
on and talk science too i guess but uh
yeah come and find us at duke or find us
on on twitter that's the easiest thing