0:00

Welcome to Huberman Lab Essentials, where

0:02

we revisit past episodes for the

0:04

most potent and actionable science-based tools

0:07

for mental health, physical health, and

0:09

performance. I'm Andrew Huberman and

0:11

I'm a professor of neurobiology and

0:13

ophthalmology at Stanford School of Medicine.

0:15

This podcast is separate from my

0:17

teaching and research roles at Stanford.

0:20

It is, however, part of my

0:22

desire and effort to bring zero

0:24

cost to consumer information about science

0:26

and science-related tools to the general

0:28

public. Today we're going to talk

0:30

about the science of tools for fat

0:32

loss. Today's episode is mainly going

0:35

to be focused on how the

0:37

nervous system, neurons, and some of

0:39

the cells they collaborate with like

0:41

glia and macrophages, how those encourage

0:44

or can encourage accelerated

0:46

fat loss because it turns out

0:48

they can. Remember your nervous system

0:50

which includes your brain and your

0:52

spinal cord and all the connections

0:54

that they make with the organs

0:57

of the body. governs everything. The

0:59

nervous system and the role of

1:01

the brain and other neurons has

1:03

been vastly overlooked in the discussion

1:06

about losing fat. Now, I would be

1:08

remiss and I'd probably come under

1:10

a pretty considerable attack if I

1:13

didn't just acknowledge up front a

1:15

core truth of metabolic science

1:17

and also of neuroscience, frankly,

1:19

which is that Calaries in

1:22

versus calories out meaning how

1:24

many calories you ingest versus

1:26

how many calories you burn

1:28

is the fundamental and most

1:30

important formula in this business

1:32

of fat loss and weight

1:35

management in general There's simply no

1:37

way around the fact that if

1:39

you ingest far more calories than

1:41

you burn you're likely to gain weight

1:44

and a good portion of that weight

1:46

is likely to be adipose tissue fat

1:48

It's also true that if you ingest fewer

1:50

calories than you burn, that you will lose

1:52

weight and that a significant portion of that

1:54

will come from body fat. What portion

1:56

depends on the number of factors,

1:59

but that simple form... is important.

2:01

So a calorie is a calorie

2:03

as a unit of energy and

2:05

we need to accept and acknowledge

2:08

this calories in meaning calories

2:10

ingested versus calories burned formula

2:13

but the calories burned portion

2:15

is strongly influenced by a

2:18

number of things that you

2:20

can control that can greatly accelerate

2:22

or increase the amount of adipose

2:24

tissue or the proportion of adipose

2:27

tissue that you burn in response

2:29

to exercise and food. Today we're

2:31

going to talk about the fact

2:33

that your body fat of various

2:36

kinds and there are several kinds

2:38

of body fat. are actually innervated

2:40

by neurons. Neurons connect to your

2:42

body fat and can change the

2:44

probability that that body fat will

2:47

be burned or not. So your

2:49

nervous system is the master controller

2:51

of this process. And it plays

2:53

a strong role in the calories

2:56

out, the calories burned component. So

2:58

let's talk about fat utilization. Let's

3:00

talk about how fat is converted

3:02

into energy, which is sometimes also

3:04

called fat burning. There's two

3:06

parts to this process. One

3:09

is fat mobilization. And the second

3:11

is fat oxidation or

3:13

utilization. And that's a process

3:15

called lipolysis. Fat cells can

3:17

be visceral around our viscera

3:20

or organs or they can

3:22

be subcutaneous under our skin.

3:24

Stored fat has two parts that

3:26

are relevant here. It's got the

3:28

fatty acid part and that's the part

3:30

that your body can use and that's

3:32

attached to something called glycerol and they're

3:35

linked by a backbone. To mobilize fat

3:37

you gotta break the backbone between glycerol

3:39

and these fatty acids. Okay, that's accomplished

3:41

by an enzyme called lipase but

3:43

you can forget all that if you want.

3:45

Remember we're just trying to mobilize fat. So

3:48

the first step is to get those fatty

3:50

acids moving around. in the bloodstream to

3:52

get them out of those fat

3:54

cells and then they can travel

3:56

and be used for energy. They're

3:58

going to go. into cells that

4:01

can use them for energy. And

4:03

once they are inside those cells,

4:05

they're still not burned up. You

4:07

need to oxidize them. They need

4:10

to be moved into the mitochondria.

4:12

And then they can be converted

4:14

into ATP into energy. So just

4:17

to really zoom out again to

4:19

make sure I don't lose anybody,

4:21

you got to mobilize the fat,

4:23

then you have to oxidize the

4:26

fat. And many of the things

4:28

that the nervous system can do

4:30

is to... increase the mobilization of

4:32

fat, but also the oxidation of

4:35

fat. So what are these neurons

4:37

that connect to fat doing? What

4:39

are they releasing exactly? How do

4:41

they actually increase fat mobilization? And

4:44

how do they increase fat oxidation,

4:46

burning of fat? Well, there are

4:48

a couple of things that they

4:51

release that encourage that process. And

4:53

the main one that you need

4:55

to know about is epinephrine or

4:57

adrenaline. The conversion of these fatty

5:00

acids into ATP in the mitochondria

5:02

of cells is favored by adrenaline

5:04

Okay, and adrenaline is released from

5:06

two sources Adrennal is released from

5:09

the adrenal glands which sit atop

5:11

our kidneys in our lower back

5:13

and it's also released From the

5:15

so-called sympathetic nervous system, although that

5:18

name is a bit of a

5:20

misnomer Because it has nothing to

5:22

do with sympathy has to do

5:25

with stimulating alertness and promoting action

5:27

of the body It was thought

5:29

for a long time that adrenaline

5:31

swimming around in your body of

5:34

when you're fasted because fasting can

5:36

increase adrenaline or when you're engaging

5:38

in intense exercise or when you're

5:40

stressed is going to promote fat

5:43

oxidation That's actually not the case

5:45

The adrenaline that stimulates fat oxidation

5:47

the burning of fat is coming

5:49

from neurons that actually connect to

5:52

the fat It's a local process

5:54

and this is very important Because

5:56

it means that what you do

5:59

the specific patterns of movements and

6:01

the specific environment you create that

6:03

can stimulate these particular neurons to

6:05

activate fat, meaning to release fat,

6:08

to mobilize it, and then to

6:10

burn it is going to be

6:12

a powerful lever that you can

6:14

use in order to increase fat

6:17

loss. Okay, so let's talk about

6:19

how to activate the nervous system

6:21

in ways that it promotes more

6:23

liberation, movement, mobilization of fat, and

6:26

more oxidation of fat. I'd like

6:28

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8:03

one of the most powerful ways

8:06

to stimulate epinephrine, which is also

8:08

called adrenaline, from these neurons, is

8:10

through movement. The type of movement

8:12

that I'm referring to is extremely

8:15

subtle, is extremely subtle. Shivering is

8:17

a strong stimulus for the release

8:19

of adrenaline, epinephrine into fat, and

8:21

the increase in fat oxidation and

8:24

mobilization. And there are other subtle

8:26

forms of movement that can greatly

8:28

increase fat metabolism and fat loss.

8:30

There was a group in England

8:33

during the 1960s and 70s that

8:35

discovered a pathway by which subtle

8:37

forms of movement can greatly increase

8:40

fat loss. This is the work

8:42

of Rothwell and Stock. It's very

8:44

famous in the Thermogenesis literature. And

8:46

I learned about this early on

8:49

when I was an undergraduate and

8:51

I asked, how did they come

8:53

across this? And here's how the

8:55

story goes. They were aware that

8:58

some people overeat, even just a

9:00

little bit, and they seem to

9:02

accumulate extra adipose tissue. Now this

9:04

is long before all the discussions

9:07

about microbiome and hormone factors and

9:09

you know as long before it

9:11

many of the hormone factors besides

9:14

insulin had even been discovered. What

9:16

they did was they examined people

9:18

who over ate and did not

9:20

gain weight. And what they observed

9:23

was that those people engaged in

9:25

lots of subtle movement throughout the

9:27

day. In other words, they were

9:29

fidgeters. And that's what they called

9:32

them. And in 2015 and again

9:34

in 2017 there have been studies

9:36

that have explored this using some

9:38

modern metabolic tracking and indeed simply

9:41

moving a lot being a fidgeter

9:43

bouncing your knee standing up and

9:45

pacing several times or many times

9:48

throughout the day led to considerable

9:50

amounts of fat loss and weight

9:52

loss when people were ingesting the

9:54

same amount of food. If they

9:57

overate, they were able to compensate

9:59

and burn off that food. So

10:01

for people that are overweight who

10:03

are kind of a verse to

10:06

exercise, fidgeting might actually be a...

10:08

good entry point. Now, that's great,

10:10

and you can think about the

10:12

protocols, but I want to nest

10:15

that protocol in what I said

10:17

before, which is that fat is

10:19

controlled by these neurons and the

10:22

epinephrine they release. Those subtle movements

10:24

of our core musculature, not just

10:26

the core, but all our limbs

10:28

in our in our musculature, those

10:31

low level movements. They trigger epinephrine

10:33

release from these neurons and they

10:35

stimulate the mobilization of fat. And

10:37

then that fat is oxidized at

10:40

higher rates. So what's the protocol?

10:42

Fidget. If you're really interested in

10:44

burning calories and you already exercise,

10:47

you want to burn more or

10:49

you don't have the opportunity to

10:51

exercise or you're a versed exercise

10:53

for whatever reason. Fidgeting movements, staccato

10:56

movements, standing up, walking around, pacing,

10:58

all the sort of nervous activities

11:00

that we're so critical of and

11:02

other people and sometimes in ourselves

11:05

are actually mobilizing and oxidizing a

11:07

lot of fat and a lot

11:09

of energy. And while this probably

11:11

won't compensate for chronic overeating, the

11:14

caloric burn from this is considerable

11:16

and very likely can offset a

11:18

meal that had excessive calories or

11:21

a kind of steady state of

11:23

a cumulative of eating too much.

11:25

Now it should make sense why

11:27

shivering is one of the strongest

11:30

stimuli that one can incorporate to

11:32

stimulate fat loss. Now, shivering is

11:34

almost always associated with cold. We

11:36

think shivering, we think cold because

11:39

when we get cold, we shiver.

11:41

And there are two ways that

11:43

shivering can increase fat loss. And

11:45

there are several ways that you

11:48

can use shivering, you can leverage

11:50

shivering, and you can leverage cold

11:52

to accelerate fat loss, but you

11:55

have to do it correctly. And

11:57

most of the people that are

11:59

using. cold and frankly suggesting cold

12:01

as a means to increase metabolism

12:04

fat loss are suggesting the exact

12:06

wrong protocol. Most people out there

12:08

are using cold exposure, typically by

12:10

taking cold showers or by getting

12:13

into cold water of some other

12:15

kind, a lake or a cold

12:17

bath or an ice bath. since

12:19

today we're talking about accelerating fat

12:22

loss through the use of science-based

12:24

tools, I want to emphasize a

12:26

study that was published in Nature

12:29

just a couple years ago showing

12:31

exactly how cold increases metabolism and

12:33

fat loss. So we have several

12:35

kinds of fat, three kinds in

12:38

fact. We have white fat, white

12:40

adipose tissue, and we have brown

12:42

fat or brown adipose tissue. And

12:44

there's a third kind which is

12:47

beige adipose tissue. White fat is

12:49

the type that we traditionally think

12:51

of as fat, subcutaneous fat. And

12:53

it is not particularly rich in

12:56

mitochondria. It is there as an

12:58

energy storage site. And we have

13:00

to mobilize the fat out as

13:03

we talked about before and burn

13:05

it up elsewhere. Brown fat largely

13:07

exists between our shoulder blades and

13:09

on the back of our neck.

13:12

between the scapulae and it's rich

13:14

with mitochondria which is why it's

13:16

called brown fat and brown fat

13:18

has a particular biochemical cascade whereby

13:21

it can take food energy and

13:23

it can take food basically break

13:25

it down and convert it into

13:27

energy within those cells but unlike

13:30

fatty acids from white fat which

13:32

have to travel elsewhere get broken

13:34

down and it and convert into

13:37

a TTP etc. etc. Use by

13:39

the mitochondria rather brown fat is

13:41

Thermogenic it can actually use energy

13:43

directly cold causes the release of

13:46

adrenaline from your dream and it

13:48

causes the release of epinephrine from

13:50

these neurons that connect to fat.

13:52

The paper published in Nature shows

13:55

that it is shivering itself that

13:57

causes the brown fat to increase

13:59

your burning, your burn rate and

14:01

your metabolism. And it works like

14:04

this. When you get into cold.

14:06

and you shiver, the shivering, those,

14:08

that low level movement of the

14:11

muscle, those small movements, triggers the

14:13

release of a molecule called sucanate,

14:15

S-U-C-C-I-N-A-T-E, sucanate, and sucanate acts on

14:17

the brown fat to increase brown

14:20

fat thermogenesis and fat burning overall.

14:22

The question then is how long

14:24

to get into that cold environment

14:26

and how cold should that environment

14:29

be? So first let's talk about

14:31

how long to get into that

14:33

cold environment. It turns out that

14:36

if you want to trigger the

14:38

shiver, what you want to do

14:40

is to get into the cold

14:42

and then get out of the

14:45

cold and typically not dry off.

14:47

and then get back into the

14:49

cold and out of the cold.

14:51

That will definitely stimulate more shivering

14:54

than just getting into the cold

14:56

itself. So how cold should it

14:58

be? And look, if you get

15:00

into water that's very, very cold,

15:03

it can actually shock your heart.

15:05

It can actually give you a

15:07

heart attack if it's truly, truly

15:10

ice cold and you're not adapted

15:12

to that. So proceed with caution,

15:14

please. I'm not a physician and

15:16

I don't want to see anyone

15:19

get hurt. But just cold enough

15:21

to be uncomfortable is a good

15:23

place to start. So for some

15:25

of you, that's going to be

15:28

60 degrees. For some of you,

15:30

that's going to be 55 degrees.

15:32

For some of you, it's going

15:34

to be high 30s, right? Depends

15:37

on how cold adapted you are.

15:39

So what you need to do

15:41

is find a temperature that you

15:44

can get into one to five,

15:46

probably one to three times a

15:48

week, if you really want this

15:50

to accelerate fat loss. from one

15:53

to three minutes and then get

15:55

back into the cold. So here's

15:57

a potential kind of sets reps

15:59

protocol that you can play with.

16:02

Find a temperature that induces shiver

16:04

for you. That's going to vary

16:06

depending on your cold tolerance and

16:08

how cold adapted you are. One

16:11

to three maybe five times a

16:13

week. Get in until you or

16:15

get under the shower or whatever

16:18

it is until you start to

16:20

shiver, genuinely shiver. Then. After about

16:22

a minute or so get out

16:24

spend one to three minutes out,

16:27

but don't try off get back

16:29

in For anywhere from one to

16:31

three minutes, but try and access

16:33

the shiver point again, and you

16:36

might do three repetitions of that

16:38

So it's three times in and

16:40

three times out total I'd like

16:43

to take a quick break and

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I'd like to move to exercise

18:57

and how particular timing and types

18:59

of exercise can vastly improve fat

19:01

loss. The topic of exercise is

19:03

a kind of controversial one. I

19:06

think the most simple way, the

19:08

most fluid way to have this

19:10

conversation about exercise and fat loss,

19:12

is in terms of three general

19:14

types of training. And those are

19:17

high intensity interval training, so high

19:19

intensity interval training, sprint interval training.

19:21

So that's gonna be very high

19:23

intensity or SIT or moderate intensity

19:25

continuous training. M-I-C-T. So we've got

19:28

hit, sit, and micked. If you'd

19:30

like to map this to VO-2

19:32

Max. SIT, this sprint interval training,

19:34

was defined as all out greater

19:36

than 100% of VO2 max, bursts

19:39

of activity that last 8 to

19:41

30 seconds, interspersed with less intense

19:43

recovery periods. This would be sprinting

19:45

downfield for 8 to 30 seconds,

19:47

then maybe walking back for about

19:50

a minute or two, and then

19:52

sprinting again and then continuing. So

19:54

that would be SIT. HIT. It's

19:56

defined as submaximal, so 80 to

19:58

100% of VO2 Max bursts of

20:01

activity that last 60 to 240

20:03

seconds, interspersed with less intense recovery

20:05

periods, and my. This moderate intensity

20:07

continuous training is steady state cardio,

20:09

sometimes called zone two cardio these

20:12

days on the internet, which is

20:14

performed continuously for 20 to 60

20:16

minutes at moderate intensity of 40

20:18

to 60% of VO2 Max. Or

20:20

if you prefer heart rate, 55

20:23

to 70% of Max heart rate.

20:25

Okay, so we can think about

20:27

high, medium, and low intensity exercise,

20:29

although low intensity usually means that

20:31

you could carry on a conversation

20:34

or maybe you'd have to gasp

20:36

every few steps or so while

20:38

trying to talk and run. That's

20:40

I think going to be the

20:42

most useful way to have this

20:45

conversation that we're having now because

20:47

there's so many different forms of

20:49

exercise that people do and intensity

20:51

is important. Let's ask the question

20:53

that I think many of people

20:56

are wondering about. which is, is

20:58

it better, meaning you burn more

21:00

fat if you do your exercise

21:02

fasted? And fasted in this respect,

21:04

could be that you wake up

21:07

in the morning, you've been fasting

21:09

all night, you just hydrate, and

21:11

you exercise. For short periods of

21:13

training, it doesn't really seem to

21:15

matter whether or not you eat

21:18

before training or you don't, if

21:20

your goal is fat oxidation. At

21:22

a period of about 90 minutes.

21:24

of moderate intensity exercise. There's a

21:26

switchover point whereby if you ate

21:29

before the exercise, you will reduce,

21:31

excuse me, you will burn far

21:33

less fat from the 90 minute

21:35

point onward than you would if

21:37

you had gone into the training

21:40

fasted. Now there are also studies

21:42

that. point to the fact that

21:44

you don't have to wait to

21:46

90 minutes in order to get

21:48

this enhanced fat burning effect. If

21:51

one does high intensity training or

21:53

even the very high intensity forms

21:55

of train like sprints or squats

21:57

or deadlifts or any kind of

21:59

activity that can't be maintained for

22:02

more than these, you know, or

22:04

I would say up to 60

22:06

seconds. So a set of lifting

22:08

weights, repeated, repeated, if that's done

22:10

for anywhere from 20 minutes, so

22:13

weight training, or power lifting, or

22:15

these kinds of things, or kettle

22:17

ball swings, or up to 60

22:19

minutes, well then the switchover point

22:21

in which you can burn more

22:24

fat if you go into that

22:26

fasted comes earlier. And this makes

22:28

sense because there's nothing wholly about

22:30

the 90 minute point for medium

22:32

intensity. zone 2 cardio. That 90

22:35

minute point is the point in

22:37

which the body shifts over from

22:39

mainly burning glycogen, basically sugar that

22:41

comes from muscles or the liver,

22:43

and realizes this is going on

22:46

for a while. I'm going to

22:48

shift over to a storage site

22:50

fuel that is in reserve, like

22:52

body fat. This is something that

22:54

has to do with the milieu

22:57

of various hormones. What has to

22:59

happen is insulin has to go

23:01

down far enough. So if you

23:03

ate before the exercise, you'd have

23:05

an increase in insulin. If you

23:08

ate carbohydrates, you'd have a bigger

23:10

increase in insulin. Fat and proteins

23:12

indeed will have lower amounts of

23:14

insulin and fasting will give you

23:16

the lowest amount of insulin. Well

23:19

then that switchover point is gonna

23:21

come earlier in the exercise. Think

23:23

about if you were to do

23:25

something high intensity for 20, 30,

23:27

40 minutes, so maybe lift weights

23:30

and then get into zone two

23:32

cardio, if you were fasted, the

23:34

literature says that you're going to

23:36

burn more body fat per unit

23:38

time, then if you had eaten

23:41

before or during the exercise. So

23:43

what does this mean? This means

23:45

if you want to burn more

23:47

body fat, if it's in your

23:49

protocols and you've been approved to

23:52

do this safely, Exercise intensely for

23:54

20 to 60 minutes. The higher

23:56

the intensity, obviously the shorter that

23:58

bout is going to be, and

24:00

then move over into zone two

24:03

cardio. And if you do that

24:05

fasted, then indeed you will burn

24:07

a higher percent. of body fat.

24:09

But if you can't even get

24:11

to the exercise, if you're somebody

24:14

who just can't do the training

24:16

at all, you're unwilling to or

24:18

you're incapable of training unless you

24:20

eat something, then obviously eating something

24:22

makes the most sense. And what

24:25

you eat prior to exercise, that's

24:27

a whole other biz that people

24:29

argue about and fight about whether

24:31

or not you should go into

24:33

it with low carbohydrates or higher

24:36

cover, all of that. But in

24:38

general, the theme there is very

24:40

simple, which is body fat. This

24:42

could be distilled into a simple

24:44

protocol whereby three or four times

24:47

a week. You do high intensity

24:49

training followed by either nothing or

24:51

followed by low intensity training, especially

24:53

if you're able to do that

24:55

fasted. And I should just mention

24:58

that none of this stuff about

25:00

fasted is about performance. If you

25:02

want to perform really well, you

25:04

want to, this is for reasons

25:06

of performance and you want to,

25:09

you know, it's for a sport

25:11

or a competition, it's not for

25:13

body fat purposes. Well then. all

25:15

this kind of falls away and

25:18

is modified by what's ideal to

25:20

eat for performance. But what we're

25:22

talking about today is how to

25:24

optimize body fat, body fat loss.

25:26

So I think you get the

25:29

principle now, but you should all

25:31

be asking yourselves, as scientists of

25:33

yourselves, why would it be that

25:35

certain patterns of exercise would lead

25:37

to more or less fat loss?

25:40

And again, it has to do

25:42

with the neurons, it has to

25:44

do with how we engage the

25:46

nervous system. So while non-exercise activity

25:48

induced thermogenesis, neat, the fidgeting, and

25:51

cold can induce thermogenesis by engaging

25:53

shiver type movement or low level

25:55

movements, big movements that are of

25:57

very high intensity, meaning they require

25:59

a lot of effort, deploy a

26:02

lot of adrenaline, epinephrine from our

26:04

neurons, and signal particular types and

26:06

amounts of. fat thermogenesis, fat oxidation.

26:08

Whereas low level intensity exercise, low

26:10

or moderate intensity exercise, you know,

26:13

walking, running, biking, where you can

26:15

do that easily, there's not. very

26:17

much adrenaline release. So adrenaline, aka

26:19

epinephrine, is really the final common

26:21

path by which movement of any

26:24

kind, whether or not it's low

26:26

level shiver, or whether or not

26:28

it's lifting a barbell, sprinting up

26:30

a hill, or doing a long

26:32

bike ride, adrenaline is the effector

26:35

of fat loss. It's the trigger

26:37

and it's the effector. So now

26:39

I want to turn our attention

26:41

to compounds that increase epinephrine and

26:43

adrenaline as well as compounds that

26:46

work outside the the adrenaline epinephrine

26:48

pathway to increase the rates of

26:50

fat loss. I almost always save

26:52

compounds and supplements and things of

26:54

that sort to the end because

26:57

I do believe that people should

26:59

look first toward behavioral tools and

27:01

an understanding of the science before

27:03

they look toward a supplement or

27:05

a particular thing that they can

27:08

extract from diet. This is mainly

27:10

to try and shift people away

27:12

from the kind of magic pill

27:14

phenomenon or the idea that there

27:16

is a magic pill because there

27:19

really isn't and frankly there never

27:21

will be. But there are some

27:23

compounds that can greatly increase fat

27:25

oxidation and mobilization and mobilization and

27:27

understanding which compounds increase oxidation or

27:30

mobilization can be very useful if

27:32

your goal is to accelerate fat

27:34

loss. I'd like to take a

27:36

quick break and thank one of

27:38

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27:41

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27:43

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27:52

that proper hydration is critical for

27:54

optimal brain and body function. In

27:56

fact, even a slight degree of

27:58

dehydration can diminish your cognitive and

28:00

physical performance to a considerable degree.

28:03

It's also important that you're not

28:05

just hydrated, but that you get

28:07

adequate amounts of electrolytes in the

28:09

right ratios. Drinking a packet of

28:11

elements dissolved in water makes it

28:14

very easy to ensure that you're

28:16

getting adequate amounts of hydration and

28:18

electrolytes. To make sure that I'm

28:20

getting proper amounts of both, I

28:22

dissolve one packet of element in

28:25

about 16 to 32 ounces of

28:27

water when I awake. up in

28:29

the morning and I drink that

28:31

basically first thing in the morning.

28:33

I'll also drink a packet of

28:36

element dissolved in water during any

28:38

kind of physical exercise that I'm

28:40

doing, especially on hot days when

28:42

I'm sweating a lot and losing

28:44

water and electrolytes. There are a

28:47

bunch of different great-tasting flavors of

28:49

element. There are a bunch of

28:51

different great tasting flavors of element.

28:53

I like the watermelon, I like

28:55

the citrus. If you'd like to

28:58

drink element, spelled L-M-N-T. So it's

29:00

drink element.com/Huberman to claim a free

29:02

sample pack. There are things that

29:04

people can ingest that will allow

29:06

them to oxidize more fat. And

29:09

that occurs mainly by increasing the

29:11

amount of epinephrine that is released

29:13

from neurons that innervate fat tissue.

29:15

One of the more common ones

29:17

is one that you may already

29:20

be using, which is caffeine. It's

29:22

well established that caffeine can enhance

29:24

performance if you're caffeine adapted. If

29:26

you're caffeine adapted, Caffeine for burning

29:28

more fat for oxidizing and mobilizing

29:31

more fat is an interesting one.

29:33

It can be effective at dosages

29:35

up to 400 milligrams. 400 milligrams

29:37

is roughly a cup and a

29:39

half of coffee. or two cups

29:42

of coffee. Nowadays, there's a lot

29:44

more caffeine in coffee. So if

29:46

you go to a typical cafe

29:48

and you were to get their

29:50

medium size, that would have close

29:53

to a gram of caffeine, which

29:55

is why if you're a regular

29:57

caffeine consumer and you don't get

29:59

that gram of caffeine in your

30:01

coffee each day, you will get

30:04

a headache. It can cause constriction

30:06

and dilation of blood vessels in

30:08

ways that's complicated, but you'll get

30:10

a headache. Caffe can enhance the

30:12

amount of fat that you burn.

30:15

in any duration of exercise and

30:17

it can shift the percentage of

30:19

fat that you oxidize compared to

30:21

glycogen. Unless you take that caffeine

30:23

and it ramps you up so

30:26

much that you're training really really

30:28

intensely. The bottom line is if

30:30

you like caffeine and you can

30:32

use it safely, ingesting somewhere between

30:34

100 and 400 milligrams of caffeine

30:37

prior to exercise, somewhere between 30

30:39

to 40 minutes before exercise, can

30:41

be beneficial if we're talking about

30:43

fat oxidation, burning more body fat.

30:45

And if caffeine is the kind

30:48

of the entry point for most

30:50

people of using compounds to increase

30:52

the rate or percentage of fat

30:54

loss in exercise and even at

30:56

rest, What are some of the

30:59

other things that are useful and

31:01

interesting? Well, in terms of tools

31:03

that are actionable and have reasonable

31:05

safety margins, I've talked before about

31:07

something called GLP1. This is something

31:10

that can be triggered by the

31:12

ingestion of Yerba Matte. Matte increases

31:14

GLP1. GLP1 is in the glucagon

31:16

pathway. So let's just quickly return

31:18

to our biochemistry. As you recall,

31:21

fat is mobilized from body fat

31:23

stores. and then it's burned up,

31:25

it's oxidized in cells. It actually

31:27

needs to be converted into ATP

31:29

and those fatty acids are essentially

31:32

converted into ATP in the mitochondria

31:34

of the cell. High insulin prevents

31:36

that from happening and glucagon facilitates

31:38

that process. Glucagon facilitates that process

31:40

through increases in GLP1. The short

31:43

takeaway is Matte increases GLP1 and

31:45

yes increases the percentage of fat

31:47

that you'll burn. It increases fat

31:49

burning. And that is especially true,

31:51

it turns out, from the scientific

31:54

literature, if you ingest Matte prior

31:56

to exercise of any kind. So

31:58

if you want to burn more

32:00

fat, drinking Matte before exercise is

32:02

good. Drinking it at rest when

32:05

you're not exercising will also help

32:07

shift your metabolism toward. enhanced burning

32:09

of fat by increasing fat oxidation.

32:11

There's a whole category of pharmaceuticals

32:13

that's being developed right now that

32:16

are in late stage trials or

32:18

are in use for the treatment

32:20

of diabetes, which capitalize on this

32:22

GLP1 pathway. Go by various names

32:24

and. There are people on the

32:27

internet who are selling these things.

32:29

They are prescription drugs and I

32:31

want to emphasize that they are

32:33

prescription drugs and you obviously wouldn't

32:35

want to use any of these

32:38

without a prescription and a requirement.

32:40

It does seem that they are

32:42

effective for the treatment of certain

32:44

kinds of diabetes and lead to

32:46

fairly significant weight loss and reduction

32:49

in appetite. So this is kind

32:51

of the modern version of GFP1.

32:53

pharmaceuticals of GLP1 metabolism are drugs

32:55

such as semmatical, I can never

32:57

pronounce this, can't seem to pronounce

33:00

many things it seems, semaglutide is

33:02

the the way I would pronounce

33:04

it, in any case this compound

33:06

increases GLP1, it's actually a GLP1

33:08

analog in some cases, and they

33:11

go by various types of trade

33:13

names. And again, the semaglutide is

33:15

the prescription version of the, it's

33:17

kind of the heavy artillery J

33:19

LP1 stimulant and again should be

33:22

only explored with a prescription. So

33:24

those are the compounds that that

33:26

really increase fat oxidation directly. There

33:28

are going to be a number

33:30

of things that impact insulin and

33:33

glucagon that are going to shift

33:35

the body toward more fat burning.

33:37

And so for instance. burberine, which

33:39

comes from a plant, or metformin

33:41

are compounds that are now in

33:44

kind of growing use for reducing

33:46

blood glucose. They are very potent

33:48

at reducing blood glucose, which will

33:50

reduce insulin because the job of

33:52

the hormone insulin is to essentially

33:55

manage glucose in the bloodstream. So

33:57

there are huge gallery of compounds

33:59

that will reduce insulin and thereby

34:01

can increase fat oxidation. And that's

34:03

because, as I mentioned before, fat

34:06

oxidation, this conversion of fatty acids

34:08

into ATP in the mitochondria, is

34:10

inhibited by insulin. So if you

34:12

keep insulin low, you're going to

34:14

increase that process, which brings us

34:17

full circle back to the issue

34:19

of diet and nutrition. There is

34:21

really solid evidence from the. Gardner

34:23

lab at Stanford and from other

34:25

labs showing that when you look

34:28

at different diets, you look at

34:30

low-fat diets, high-fat diets, keto diets,

34:32

intermittent fasting, provided people stick to

34:34

their particular diet, it doesn't really

34:36

matter which diet you follow. You

34:39

can still get a caloric deficit

34:41

and you get weight loss. Adherence,

34:43

however, is always an issue. And

34:45

so what I always say is...

34:47

that you want to use the

34:50

eating plan that is obviously beneficial

34:52

to your health, but the one

34:54

that allows you to adhere to

34:56

whatever it is that the particular

34:58

nutrition protocol is, right? If you

35:01

can't stick with something, then it's

35:03

not very worthwhile. But from the

35:05

purely scientific standpoint, there's also an

35:07

advantage to keeping insulin low. Now

35:09

that doesn't necessarily mean you go

35:12

to zero carbohydrate. I've talked before,

35:14

my preferred way of eating is

35:16

to go lower no carbohydrate throughout

35:18

the day for alertness to get

35:20

that adrenaline release and the focus

35:23

that goes with it, etc. and

35:25

the ability to think and move

35:27

and do all the things I

35:29

need to do during the day

35:31

and then I eat carbohydrates at

35:34

night because it facilitates the transition

35:36

to sleep. That's what works for

35:38

me. But when insulin is low,

35:40

you do place your system. in

35:42

a position to oxidize more fat.

35:45

And so that's why I think

35:47

a lot of people do see

35:49

benefit from lower carbohydrate or moderate

35:51

carbohydrate diets, because when insulin is

35:53

low, you are in a position

35:56

to oxidize more fat, both from

35:58

exercise and at rest. So once

36:00

again, we've covered an enormous amount

36:02

of material. We've talked about the

36:04

science of fat loss. And in

36:07

particular. we've explored this topic from

36:09

the perspective of the nervous system,

36:11

how neurons and in particular the

36:13

release of things like adrenaline, epinephrine

36:15

can facilitate fat mobilization and oxidation.

36:18

We talked about neat, fidgeting, this

36:20

non-exercise type movement that can greatly

36:22

increase caloric burn and why that

36:24

is. We talked about shiver, another

36:26

form of non-exercise movement that can

36:29

really increase both caloric expenditure due

36:31

to the shiver, due to the

36:33

movement, as well as increase thermogenesis,

36:35

the heating up of the body

36:37

through things like brown fat, and

36:40

even the conversion of white fat

36:42

to brown fat, which is a

36:44

good thing if you want to

36:46

oxidize fat. We talked about cold

36:48

as a particular stimulus to induce

36:51

shiver and how to use getting

36:53

into and out of cold as

36:55

a way to stimulate shiver and

36:57

avoid cold adaptation so that you

36:59

continue to oxidize and burn fat

37:02

if that's your goal. Talked about

37:04

exercise, how rather than thinking about

37:06

cardiovascular or weight training exercise, that

37:08

we should perhaps look through the

37:10

lens of this adrenaline system and

37:13

how it interacts with fat stores

37:15

and think about low medium or

37:17

high intensity exercise, whether or not

37:19

we show up to that fasted

37:22

or not. Turns out showing up

37:24

to that fasted can be useful

37:26

if you start with high intensity.

37:28

movements and then move into lower

37:30

intensity type exercise. If you're going

37:33

to go long duration, it probably

37:35

doesn't matter unless you're exercising longer

37:37

than 90 minutes, whether or not

37:39

you eat or not. We talked

37:41

about caffeine as a stimulant and

37:44

a stimulus for epinephrine and adrenaline

37:46

release. as a way to access

37:48

more fat metabolism. And last but

37:50

not least, I want to thank

37:52

you for your time and attention

37:55

today, and thank you for your

37:57

interesting science. You