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it comes to losing weight, almost

1:00

everyone seems to agree on one thing.

1:10

It's hard. And if you've ever tried to

1:12

do it, no matter how many pounds you are aiming to

1:14

shed, maybe it felt

1:16

unnatural. Impossible even. Like

1:19

you were just bound to fail. Almost

1:21

like your body and your brain were actively

1:23

working against your goals. Like they were fighting

1:26

to keep on the weight. Now,

1:30

if that sounds familiar, I'm here

1:32

to tell you that you're probably not imagining

1:34

it. In fact, much of what I just

1:36

described happening inside your body and your brain

1:39

is actually outside your control.

1:42

In fact, according to one 2021 study, it is common for

1:46

people who lose 10% of their body

1:48

weight to regain most of it within a

1:51

year. And that same study showed

1:53

that they're likely to regain all of it within

1:55

five years. And after that kind of loss and

1:57

gain, it's often hard to get back to your

1:59

brain. harder to ever lose it

2:01

again. I

2:03

know that's not what you want to hear,

2:06

but the fact is that the weight loss

2:08

struggle is real. At first,

2:10

you'll start asking questions. Am I just not

2:12

eating the right things? Am I just not

2:14

putting enough hours at the gym? Am I

2:16

just not trying hard enough? Then

2:18

you're going to ask, is there

2:20

something that's wrong with me? But

2:23

what if it's not? What if hundreds

2:25

of thousands of years of evolution are

2:28

actually conspiring against you? We

2:30

evolved not to lose weight intentionally. That's

2:34

Professor Daniel Lieberman. He's

2:36

a paleoanthropologist who teaches human

2:38

evolutionary biology at Harvard. What

2:41

that means is that he's really interested in

2:43

why the body looks and functions the way

2:45

it does. All animals need some

2:47

fat, but humans have evolved to

2:50

have exceptionally high levels of fat, even thin

2:52

humans. So we

2:54

are under exceptional

2:57

biological pressure always

2:59

to put it on and keep it as long as

3:02

we have it for when we need it. Now,

3:05

of course, our individual metabolism, our genetics,

3:07

our habits do play a role in

3:09

our weight and how we manage it.

3:12

Even Professor Lieberman, he's a marathon runner

3:14

who has run the Boston Marathon not

3:16

once, not twice, but 13 times. It'll

3:20

be my 14th year this year. Yeah. That's

3:23

incredible. Yeah, it's kind of stupid actually.

3:25

Okay. Is it stupid? Well,

3:27

it's not stupid, but I mean, you know, we never evolved

3:29

to stand on one line and run 26.2 miles

3:32

to another one as fast as possible. Even

3:35

he would concede though, that

3:37

all that running may not

3:39

really change what we humans evolved to

3:41

do and what we didn't evolve

3:44

to do. We are, he

3:46

says, hardwired to maintain a certain

3:48

weight. And that's in part

3:50

why the struggle is so real. What

3:53

we're adapted for fundamentally is not to be

3:55

healthy, not to be happy, not to be

3:57

nice, not to be, you know, thank you.

4:00

miss not to be anything other

4:02

than reproductively successful. Bet

4:04

you weren't expecting that. On

4:07

today's episode, I'm going to explore why

4:09

it's so hard for us as humans

4:11

to lose weight, and most

4:13

importantly, what you can do about it. I'm

4:16

Dr. Sanjay Gupta, CNN's chief

4:18

medical correspondent, and this is

4:20

Chasing Life. You

4:27

know, the basic question that Professor Daniel

4:29

Lieberman asks is why the human body

4:31

looks and functions the way it does.

4:34

How and why did we evolve this way?

4:37

And that's really important to understand,

4:39

because by understanding our evolutionary past,

4:41

we may better understand our future.

4:44

And maybe, just maybe, we can

4:46

figure out how we can work

4:48

with our bodies instead of against

4:50

them. So first, I

4:52

wanted to start with a little paleolithic

4:54

perspective. What was life

4:56

really like when we were all

4:58

hunters and gatherers? All

5:00

the food they got, they had to go

5:02

out and either hunt and gather, and that

5:05

meant every day walking around somewhere between five

5:07

to ten miles a day on average. They

5:09

sometimes had to run, they had to dig a

5:11

lot, they had to occasionally climb trees. They

5:14

had to do, you know, everything was done by hand.

5:16

They had to carry their food, they had to carry

5:18

their babies, there was no shopping carts, there was no,

5:21

you know, no machines of any sort. But

5:23

in general, hunter-gatherers tend to be

5:26

reasonably fit, but not super

5:28

fit. They're not like, you know, Tour de

5:30

France athletes. They're reasonably strong,

5:32

but they're not super strong, because muscle is expensive.

5:34

You know, you don't want to have any more

5:36

muscle than you need, because it costs a lot of

5:38

energy. They ate what

5:40

they killed, or what they grew. But

5:43

the point I think he's making is that nothing

5:45

came easy. And as a result,

5:47

no surprise, our early ancestors were

5:49

pretty fit. I

5:52

should mention that even though our ancestors started

5:55

hunting and gathering at least two million

5:57

years ago, there are still a

5:59

small number of tribes in our modern world

6:01

who live like this. And

6:03

it was actually a pretty great way to live. If

6:05

a hunter-gatherer survived childhood, they tend to live about 68

6:08

to 78 years of age. So

6:11

they do pretty well, and they tend

6:13

not to have the kinds of chronic

6:15

diseases that are common in places like

6:17

America. Heart disease is very rare to

6:19

almost non-existent. Should we aspire to

6:22

be the way that we once were? I mean, is

6:24

that a good goal? No,

6:26

I don't think so. Because

6:28

first of all, farming is here to stay. Farmed

6:31

foods are here to stay. We can learn

6:33

something from hunter-gatherers. I think one of the most

6:35

important things we can learn about them is this

6:37

concept of mismatch. Imagine you're a zebra

6:40

living out in a savannah, eating grass, and

6:42

all of a sudden somebody swoops in, puts you

6:44

in a plane, and drops you in like

6:46

northern Canada in a tundra. Like what are

6:48

you going to eat, right? You're totally mismatched to

6:51

that environment. Well, we've kind of done that

6:53

to ourselves. Try and remember

6:55

that, this idea of

6:57

the mismatch. We're not

6:59

running from wild animals anymore. We are

7:01

spending our day sitting and scrolling through

7:04

our smartphones. We're not walking

7:06

miles and miles just to find water like

7:08

we used to. Instead, we

7:10

drive, sometimes for even short distances.

7:14

Sugary food and fatty foods, which used to

7:16

be scarce sources of valuable energy, are now

7:19

not only plentiful, but within easy

7:21

reach almost all the time. The

7:24

world has changed, and our environment

7:26

has changed. But here's the point. Our

7:29

bodies are still stuck in the

7:31

past biologically. It's a

7:33

mismatch. We've

7:35

changed our world through agriculture

7:37

to some extent, but really through

7:40

industrialization. So we no longer

7:42

eat the same kinds of foods. We no longer

7:44

have the same kinds of physical activities. We have

7:46

all kinds of stress from all

7:48

the things that can add up to stress. And

7:51

the result is we get certain kinds of diseases.

7:53

And looking at hunter-gatherers and

7:55

also subsistence farmers can

7:58

help us fix the disease. figure out what those

8:01

adaptations are that we are adapted

8:03

for, what we're not adapted for and to figure

8:05

out how to meld those two worlds. And

8:08

there's an important additional point

8:11

which is that just because hunter-gatherers do it

8:13

doesn't mean it's necessarily best for us. Professor

8:16

Liebman says there are lots of

8:18

mismatches. There's almost too many to

8:20

count. There are small mismatches like

8:22

having flat feet which can occur

8:24

simply from less use or

8:27

nearsightedness. That can sometimes

8:29

happen from spending too much time inside when

8:31

you're very young and your eyes don't develop

8:33

properly as a result. And

8:35

there are big mismatches as well, which

8:38

Professor Liebman and other

8:40

evolutionary biologists call mismatch

8:42

diseases. So mismatched

8:44

diseases are defined as conditions

8:46

or diseases that are more common or more

8:49

severe when we live in

8:51

environments for which we're poorly or inadequately adapted. Now

8:54

these happen because our bodies, still stuck

8:56

in the past, are poorly

8:58

adapted for the current environment. Our

9:00

ancestors didn't have large amounts of sugar available

9:03

to them at any time, but we

9:05

do now and as a result

9:07

we're much more prone to diabetes. Same

9:09

goes for heart disease. Early humans

9:11

had to be physically active to find food

9:13

which protected us from many kinds of heart

9:16

disease, but that's definitely not the case

9:18

now. So you understand the

9:20

picture that he's painting and some of

9:22

it's going to sound pretty discouraging. But

9:24

he also reminds us there is some

9:26

good news about mismatches as well. When

9:29

you can identify a mismatch, that means you're

9:31

identifying a way to prevent the disease. And

9:33

the best way to deal with the

9:35

disease is to prevent it from happening in the first place. And

9:39

so we can modify our diets.

9:41

We can modify our physical activity levels.

9:43

We don't have to go back to

9:46

the Stone Age, but we can adapt

9:48

some lessons from the Stone Age to

9:50

the modern world we live in. You don't need

9:52

to swim the English Channel or run a marathon

9:54

to be healthy. It turns out just moderate levels

9:56

of physical activity have enormous effects. You don't have

9:58

to be a hunter-gatherer. to get

10:01

the benefits of being physically active. People

10:03

who have tried to lose weight will

10:06

almost universally tell you it is hard to do.

10:09

It's hard to lose weight. It's easy to put it on.

10:13

From an evolutionary science

10:15

standpoint, why is that?

10:18

Well, let me back up by giving it some

10:20

important facts. So humans are

10:22

an unusually fat species. Even

10:25

thin human beings, like thin hunter-gatherers,

10:27

like thin hunter-gatherer males will be

10:29

about 10 to 15% body fat. Thin

10:32

hunter-gatherer females will be like 15 to 25% body fat.

10:36

That's a very healthy, thin human body.

10:39

That is way fatter than most mammals. Typical

10:41

mammals have about 4% or 5% body fat.

10:45

Other primates don't have much fat.

10:47

We pack it on compared to

10:49

most species. And the reason for

10:51

that is that fat

10:53

plays a key role in our reproduction.

10:55

And we have a very unusual reproductive

10:58

system, whereby we, compared to chimpanzees, are

11:00

closest relatives. We have babies about

11:02

twice the rate. We have multiple babies

11:04

at the time. We have these big

11:06

brains which cost a huge amount of energy. Right now, you

11:08

and I are sitting here, one out of every five of

11:11

our breasts is paying for our brain. It's

11:13

20% of our metabolism. And a baby,

11:15

when it's born, half of its energy is paying for

11:17

its brain. It needs a lot of fat. So

11:20

human babies are born very fat because they have to

11:22

have that energy to make sure that they can keep

11:25

their brain going, because the brain doesn't store energy. You

11:27

always have to supply the brain with fat. Furthermore,

11:30

if you're a hunter-gatherer mother and

11:32

every day you need to go out and get

11:34

food for your children, both your infant and maybe

11:36

your five-year-old and maybe your eight-year-old, none of them

11:38

can really feed themselves. You need a

11:41

lot of energy. You can't just wait

11:44

for Uber Eats to deliver your

11:46

food to you. You have to go out

11:48

and exercise. You have to be physically active

11:50

to get the food necessary to overcome that.

11:52

And so we draw down on our fat

11:54

reserves when we're physically active to

11:56

produce milk, to feed our

11:59

brains, to do that. do physical activity.

12:02

Fat has always been important to

12:04

humans at an almost basic level.

12:07

After all, it's a storable energy.

12:10

It helps keep our brains working. It powers our bodies. It's

12:12

a key to reproduction, to being healthy enough to

12:14

have children, and to keep those children

12:17

alive. So it's not surprising, then,

12:19

that fat is valuable and

12:21

that our bodies want to hold on

12:23

to it whenever possible for as long

12:25

as possible for future use. It's

12:28

like money in the bank account. And so individuals

12:30

who have appropriate levels of fat did better in

12:32

our evolutionary history than those who didn't, and it

12:34

would play a really important role in human evolution.

12:37

And so we were selected to make sure that

12:39

we always could put it on because there were

12:41

always times when we had to lose it. And

12:45

at the same time, we never evolved to

12:47

lose it willfully. To go into

12:49

negative energy balance is a crisis mode, right?

12:55

Peter Lieberman gave me this analogy that

12:57

I really liked when it comes to

12:59

understanding negative energy balance. Start

13:01

off this way. Think of energy in

13:04

the form of fat, like he said, money in

13:06

the bank. So when you

13:08

spend more energy than you're taking in,

13:10

let's say you've just spent all day

13:12

hunting without any luck, you're

13:14

in negative energy balance. That's

13:16

when you lose weight. And when you're

13:18

spending less energy than you have coming in, maybe

13:21

you've been feasting and resting without having

13:23

to hunt, you're in positive

13:25

energy balance. You gain weight. And

13:28

just like your bank account, you certainly don't

13:30

want to spend more than you have.

13:33

And you want to save any extra you do

13:35

have for a rainy day. Early

13:38

humans did not want to lose weight.

13:41

And despite our best intentions, neither

13:43

do our bodies now. It's

13:45

just another example of how our bodies aren't

13:47

built for the way we live now. In

13:50

other words, it's a big mismatch.

13:54

There's even mechanisms that we've developed to

13:56

resist it. So

13:58

what happens when you die? cortisol levels

14:00

go up. Cortisol is a stress hormone. It doesn't

14:02

cause you to be stressed. It goes

14:04

up when you are stressed. And one of the

14:06

effects of cortisol is it makes you hungry. So

14:09

when you diet, you are battling at least

14:13

a dozen, if not more adaptations

14:15

that evolved over millions and millions

14:17

of generations to prevent you from

14:20

losing weight. That's so interesting. And

14:22

so, of course, it's hard because

14:24

we evolved not to lose weight

14:26

intentionally. And losing weight

14:28

requires dieting, requires tricking

14:30

your body and overcoming those adaptations

14:33

which your body is going to

14:35

fight you at every inch

14:37

of the way. And of course, it's hard.

14:39

It's really, really, really hard. We need to

14:42

be extremely compassionate towards people.

14:44

It's not about willpower. That's

14:46

an unfair characterization, I think.

14:50

Not sure about you, but I do

14:52

find it reassuring to think that this

14:54

is not just a purely personal struggle,

14:56

a lack of willpower or an individual

14:58

failure. Our bodies evolved

15:01

not to lose weight. Remember that.

15:04

And we aren't just imagining that our bodies are

15:06

fighting us. They're actually programmed

15:08

by evolution to do just that.

15:11

When we come back, Professor Lieberman

15:13

will answer if we should eat

15:16

like hunter-gatherers and how to

15:18

reframe weight loss with evolutionary biology

15:20

in mind. Anderson

15:28

Cooper is back with season two of his podcast,

15:30

All There Is. My guest is Nicole

15:32

Chung. In 2018, she published her first

15:34

bestselling memoir, All You Can Ever Know.

15:36

Nicole was given up for adoption as

15:38

an infant by her Korean parents and

15:40

raised by a white couple in Oregon.

15:43

All There Is with Anderson Cooper is about how we can

15:45

live on with loss and with love. The

15:48

book chronicles her search for her birth family.

15:50

I don't try to tell anybody else how to

15:52

grieve, but I do hope people can learn to

15:55

be gentle with themselves. I think it's necessary because

15:57

if we don't grieve, it turns into another way

15:59

of punishing. ourselves. Listen to all there

16:01

is with Anderson Cooper, wherever you get

16:03

your podcasts. Welcome

16:09

back to Chasing Life. We're

16:11

speaking with Professor Daniel Lieberman, a

16:13

paleoanthropologist about why evolution has the

16:16

deck stacked against us when it

16:18

comes to weight loss. One

16:20

popular diet you might have heard of is

16:23

the so-called paleo diet, where we try to

16:25

eat like our ancestors did. But how helpful

16:27

is that really for weight loss, and is

16:30

it even good for us? Do

16:32

you think that the way that we used to eat

16:35

as hunter-gatherers, and people refer

16:37

to this as cavemen or paleo sort of diet,

16:40

I think I know the answer. I almost certainly

16:42

know what you're going to say. But

16:44

is there a practicality at all to

16:47

trying to recreate

16:49

some of the way we used to live in our

16:52

modern day? Well,

16:54

yes and no. In

16:56

the sense that there are ways in which

16:58

our modern diet has gone really seriously awry.

17:00

But a lot

17:02

of the problems that we have with obesity

17:04

and heart disease and whatever, you don't have

17:07

to go back to the stone age to

17:09

see them not occurring. You can just

17:11

go back a few hundred years to farmers.

17:14

I mean, if you look at a traditional Mediterranean diet,

17:19

which is high in fiber, doesn't have

17:21

a lot of added sugar, and has

17:23

lots of fruits and vegetables, that

17:26

the same would be true of a traditional

17:28

Mexican diet or a traditional Asian diet or

17:30

traditional African diet. These are

17:32

super healthy diets. You don't need to eat a

17:34

paleo diet. And furthermore, there is no one paleo

17:36

diet. We just published an analysis

17:39

of the paleo diet. We found

17:41

there are 12 different tribes, hunter-gatherer

17:43

tribes from different parts of the world,

17:46

where we have really good dietary data.

17:49

And none of them match the paleo

17:51

diet. Not a single one. And

17:54

There's incredible variation. Pretty Good marketing around

17:56

the Paleo. Oh, it's serious marketing. But

17:58

The thing is, we have all... The

18:00

Eat anything I'm in your liver right? if

18:02

you eat. If you eat carbohydrate, your liver

18:04

can turn into sad. If you eat fat,

18:06

your liver can turn into carbohydrates and and

18:09

protein. Wheatley You know we evolve to eat

18:11

anything. People lived in the Arctic eating all

18:13

the meat and and or of the guns

18:15

and they were vegetarians and there are you

18:17

know. This. Amazing the variation

18:19

in human diet and how people

18:22

can kind of do okay on

18:24

and why drive diet but you

18:26

know, look. If you want

18:28

to look at healthy diet's and every culture

18:30

in the world figured out how to eat

18:32

reasonably, Healthy Diet's. All. Of them

18:34

involve a lot of plant food that

18:36

not much added sugar done of is

18:38

processed stuff that we eat today. Diversity

18:41

of foods, combinations of foods. You don't

18:43

need to go back to the Paleolithic

18:45

again, That's the short answer. From

18:48

an evolutionary prospectus, Why

18:51

do diet and exercise matter so

18:53

much? A Given the fact that

18:55

we didn't really tie it to

18:57

lose weight, we didn't really exercise

18:59

for exercise sake and our evolutionary

19:01

past. Why? Is it

19:03

so important? now? Because. Both

19:05

inactivity habitual, long term

19:07

inactivity. And obesity.

19:10

Whoever you want to define it having

19:12

too much fact, both of them are

19:14

mismatches and for different reasons. So.

19:17

Obesity. Is a mismatch because it. First

19:20

and foremost causes inflammation. You're fat cells

19:22

which technical term as a deposits are

19:24

like little bags and of of these

19:27

little bags or of your body and

19:29

as you store sat. Does. That

19:31

sells. Swell like a balloon And when those

19:33

balloons get too big by oversell a balloon

19:35

is going to rupture right? and the fat

19:37

cells are no different sets of can only

19:39

hold so much fat and you only have

19:42

so many your didn't get your check develop

19:44

more them after you're born. As

19:46

those fat cells swell, if they start

19:48

to burst, it's like cutting your skin

19:50

as they causes an inflammatory reaction and

19:53

this low level of chronic inflammation. Is.

19:56

Pernicious. It causes damage throughout

19:58

the body and the strongly

20:00

associated with heart disease which

20:02

your hypertension with Alzheimer's with

20:04

diabetes with cancer So the

20:06

information from obesity is probably

20:08

the number one reason to

20:10

be concerned and belly sad

20:12

especially concerning. So. That's one of

20:15

the mismatches. I that's the obesity mismatch rent. So

20:17

we never evolved to have that much fat and

20:19

so he never, you know and love to deal

20:21

with it right? Because our ancestors maybe they would

20:23

have loved to be that sap have enough hence

20:25

the chance to be that set. Now,

20:33

Professor Lieberman reminded us of something

20:35

that you've probably heard before. Not

20:38

all fat is the same. The

20:40

fact that sunday your arms, for

20:42

example, or on your thighs that

20:44

subcutaneous fat. And ironically, even though

20:47

it's visible and causes some of

20:49

us mental anguish, it's pretty harmless.

20:52

But it's a sad you can't see

20:54

the Sat around your organs called visceral

20:56

fat and the fat in your organs

20:58

are your muscles called a topic Sat.

21:00

That's the dangerous kind. When. Those

21:03

cells become overfilled, they become

21:05

inflamed, and we know that

21:07

chronic inflammation is strongly linked

21:09

the conditions like heart disease,

21:11

hypertension, even cancer and Alzheimer's.

21:13

So. That's why diet matters. But

21:16

then, what about exercise? Slips.

21:18

To the other side: Physical inactivity as

21:21

a mismatch. A betrayal. Physical inactivity as

21:23

much as because. Remember, you know, Your

21:26

body can take a killer and they can use

21:28

it for a certain things and is not using

21:30

the calorie at that moment. What's it? Do a

21:32

scan stored as fat and if you end up

21:34

physical inactivity can. Predispose. You towards

21:37

obesity. One of the waste bread thing

21:39

that is exercise. Exercise is not great

21:41

for losing weight but it sure is

21:43

good for helping you preventing weight gain.

21:46

That's very clear from science. But.

21:48

Exercise can also be good for

21:50

another reason, not just preventing weekend.

21:53

Professor Liebman says exercising can actually

21:55

create stress in your body. The

21:57

good Times: Yes, there is a

21:59

good kind of stress. Stick with me here for

22:02

a second. Think about it. When

22:04

you exercise, go for a run

22:06

or swim or workout on an elliptical

22:08

or whatever it is you like to do, right? You're

22:10

stressing your body. You're stressing almost every system of

22:13

your body. You cause damage to proteins.

22:15

You cause damage to your DNA. You cause damage

22:17

to your muscles. You tear them apart. You cause

22:19

cracks in your bone. I mean, I could go

22:21

on. There's like a, you heat up. Everything

22:24

you can think of that is

22:26

about exercise stressful. But since we

22:28

evolved to be physically active, our

22:30

bodies evolved mechanisms

22:33

to respond to every single one of

22:35

those stresses. And in fact, they

22:38

evolved to kind of compensate, like to

22:40

overshoot. So what do you,

22:42

what does your body do when you

22:44

exercise? Your body produces antioxidants by the,

22:46

by the gazillion, right? So you, your

22:48

exercise turns on your body's production of

22:51

powerful antioxidants. When we produce

22:53

antioxidants, we produce more than enough.

22:55

When we produce enzymes to repair our

22:58

DNA, we produce more than enough. So

23:00

we end up being better off after

23:02

the exercise than before. But

23:04

here's the rub. We never evolved not

23:06

to be physically active. It

23:08

wasn't possible in the past. So we

23:11

never evolved to turn these anti-aging mechanisms

23:13

on in the absence of physical

23:15

activity. So if you want a slow aging, exercise

23:19

is key. Exercise just turns on those

23:22

mechanisms. And in the absence, we age

23:24

faster. Our bodies

23:27

want us to do things that maybe aren't conducive

23:30

to being healthy in the modern age. We

23:32

take the elevator instead of the stairs. We

23:34

crave sugar and fat. How

23:38

do you square that? What are the takeaways

23:40

and are there things that we can learn

23:42

from our ancestors? I

23:44

think the first thing is that we have

23:46

to learn to be compassionate and stop blaming

23:48

people for doing what's normal and natural. If

23:52

you stand next to the escalator and a stairway

23:54

next to each other, most people will take

23:56

the escalator. It's an instinct. If

23:58

you put them in the Kalahari Desert, people will take it. people would take

24:00

them there too. So

24:02

instead of blaming people and making them feel bad,

24:04

we have to help people feel good

24:06

about taking the stairs and making it natural. And the same

24:09

is true of food, right? If you put a piece of

24:11

chocolate and cake in front of me and

24:13

a carrot, of course I'm gonna go

24:15

for the chocolate cake. I mean, I'm not crazy

24:17

and it's an instinct, right? It tastes better and

24:19

has more energy and it's, you know, like it's

24:22

chocolate cake. And so I

24:24

think that we have to figure out how to

24:26

engineer our worlds to help us make the

24:28

choices that we would like to make. We

24:32

evolved to be physically active for two reasons

24:34

and two reasons only, when it's necessary or

24:36

when it's rewarding. So we have to figure

24:39

out ways to help us and help each

24:41

other make physical activity necessary and rewarding. And

24:43

the same is true of food. We evolved

24:45

to eat foods in order to have as

24:48

many offspring as possible. And so we go for

24:50

energy rich foods that are high in calories and

24:52

high in fat, but we didn't have

24:55

access to that stuff very often. And so

24:57

we have to find ways to help each other make

24:59

those foods delicious and

25:02

make the foods that should be special treats,

25:04

make them just special treats. We

25:06

need to act collectively. It's a political problem partly,

25:08

but also it's a social problem. We need to

25:11

figure out ways to help each other and it's

25:13

gonna require looking in the

25:15

mirror and being compassionate and clear

25:17

minded. And also I think, you

25:20

know, an evolutionary perspective can help us. And

25:24

I think this may be the most important point, having some grace for ourselves,

25:27

for others when we think and talk about weight. And

25:30

not just because you're being kind, it's

25:33

because there are actually a lot of factors that

25:35

influence someone's weight. When

25:37

Professor Lieberman explained why humans evolved

25:40

to conserve fat, that got me thinking. That's

25:43

when our bodies are holding onto weight. They're

25:46

doing what they're supposed to do. They're functioning

25:48

to keep us alive, to store up energy,

25:50

to help us. But not necessarily to help

25:52

us look good, however you might define that.

25:55

I understand that. this

26:00

can be frustrating, even annoying for some people who

26:02

are trying to shed pounds or keep them off,

26:05

but I hope it also offers some

26:07

measure of comfort or at least some

26:09

insight as to why losing weight often

26:11

isn't easy. I hope

26:13

it also demonstrates how carefully calibrated

26:15

our bodies are, how important weight

26:18

and fat actually were to

26:20

us as humans. Without

26:22

those things, the generations that came before us

26:25

might not have survived. So

26:28

yes, we might not be

26:30

able to escape the pull of evolution, but

26:33

if you think about it, we can use

26:35

it to our advantage and even build it

26:38

into our modern day environment. Next

26:42

week on Chasing Life, we're going

26:44

to talk to an obesity expert about what

26:47

everyone seems to be buzzing about, the new

26:49

medications that help us lose weight. I

26:52

remember, I remember exactly I was in my office

26:54

reading the article about

26:56

semaglutide ozembek and my

26:59

first response was, it works, it really

27:01

works. We're going to have

27:03

an honest conversation about the benefits, the

27:05

risks, the rewards and what we

27:08

still need to learn. Chasing

27:11

Life is a production of CNN Audio. Our

27:14

podcast is produced by Aaron Matheson,

27:16

Jennifer Lai and Grace Walker. Our

27:19

senior producer and showrunner is Felicia

27:21

Patinkin. Andrea Kane is

27:24

our medical writer and Tommy Bazzarian is

27:26

our engineer. Dan D'Zula

27:28

is our technical director and the executive

27:30

producer of CNN Audio is

27:32

Steve Licti. With support

27:35

from Jamis Andrest, John Deonora,

27:37

Haley Thomas, Alex

27:39

Manisari, Robert Mathers, Laini

27:42

Steinhardt, Nicole Pessaroo

27:45

and Lisa Namaro. Thanks

27:47

to Ben Tinker, Amanda Sealy and

27:50

Nadia Kanang of CNN Health and

27:53

Katie Hinman. you