Controlling Sugar Cravings & Metabolism with Science-Based Tools
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Welcome to the huberman la podcast, where we discussed science and science space tools for everyday life. I am huberman and i'm a professor of neurobiology optio logy at stanford school of medicine. Today, we are going to discuss sugar, in particular, how our nervous system regulates our sugar intake and are seeking of sugar.

We're also going to discuss how sugar regulates our nervous system. And as you'll soon learn, sugar really impacts our brain and body by two main mechanisms. One of those mechanisms is based on the sweet taste of sugar, which itself is rewarding, even if you're not much of a sweet tooth.

I confess i'm not. Most people enjoy sweet taste more than bitter taste, and the sweet taste of sugar and its various forms is strongly reinforcing, meaning IT triggers the activation of neurons, nerve cells in the brain body that make us want to consume more of that sweet substance. Incidently, sweet taste also make us want to eat more of other substances as well.

You may be familiar with that phenomenon now. Sugar also triggered mechanisms in the brain and body based on its nutritive content, independent of its sweetness. What that means is that the actual coLoring content and the way that sugar interacts with your nervous system at a subconscious level without your awareness also impacts you're craving and seeking of sugar and other foods.

Today, we are going to discuss what happens when you just sugar in terms of your body's reaction and your brains reaction. We are also going to talk about what happens when you don't ingest enough sugar. As IT turns out, sugar is such a powerful fuel for the brain that under conditions where people don't in just enough sugar, or whether so called blood glucose, which is basically blood sugar of a particular form, gets too low, their neurons don't function as well.

That said, their conditions of very low blood hurter in which neurons can function even Better. So today we are going to talk about the ins and out, the up and downs of sugar as IT relates your nervous system. And by the end of this episode, unconfident, you have a much clear picture as to how much sugar you should be ingesting, whether not you should avoid sugars that you're currently eating.

And you will certainly understand much, much more about the energy and fuel sources that your brain relies on, which I certain will allow you to make Better informed choices about the foods you eat and avoid toward mental health, physical health and performance. Before we begin, i'd like to emphasize that this podcast is separate from my teaching and research roles at stanford. IT is, however, part of my desired effort to bring zero cost to consumer information about science in science related tools to the general public.

In keeping with that theme, I like to thank sponsors of today's podcast. Our first sponsor is athletic Greens. Athletic Greens is, in all in one, a vitamin, mineral, probiotic drink i've been taking athletic Greens since two thousand and twelve. So i'm delighted that their sponsor in the podcast, the reason I started taking athletic Greens and the reason I still take athletic Greens once or twice a day, is that IT helps me cover all of my basic nutritional to make up for any deficiencies that I might have. In addition, IT has pro biotics, which are vital for microbial on health.

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Today's episode is also brought to us by element. Element is an electoral like drink that has everything you need and nothing you do. That means the exact ratio of electronic lights are an element, and those are sodium, magnesium and parasitic, but IT has no sugar.

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If you'd like to try element, you can go to drink element, that element dot com slash huberman and you'll get a free element sample pack with your purchase. They're all delicious. So again, if you want to try element, you can go to element element t dot com slash human. Today's episode is also brought to us by waking up, waking up as a meditation APP that includes hundreds of meditation programs, mindfulness trainings, yoga eja sessions and n sdr non sleep depressed protocols.

I started using the waking up up a few years ago because even though i've been doing regular meditation since my teens, and I started doing yoga ea about a decade ago, my dad mentioned to me that he had found an APP turned out to be the waking up APP, which could teach you meditations of different durations. And they had a lot of different types of meditations to place, to bring your body into different states, and that he liked IT very much. So I gave the waking up up a try, and I too found IT to be extremely useful, because sometimes I only have few minutes to meditate.

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Again, that's waking up dot com slashed huberman to access a free thirty day trial. Okay, let's talk about sugar. Let's talk about how sugar impacts your brain and how your brain impacts your pursuit or your avoidance of sugar.

Let's get a few things out of the way first. The first thing is that there's nothing inherently bad about sugar. I know the word sugar gets a bad wrap nowaday. And indeed, you're going to hear over and over again during this podcast that consuming a lot of refined sugars, in particular high fractus corn syrup, is known to have a very large number of bad effects on the brain and body.

I don't know that there's anyone that really debates that anymore, even if we just agree, and I think we should all agree on the so called calories in, calories out principle, right? It's a principal of thermal dynamics that if we in just more energy than we burn, we are going to gain weight. If we in just less energy than we burn, we are generally going to lose weight.

And if the two things are imbaLance, injustice and burning of energy, well, then we're going to maintain weight. So everyone agrees on that. I agree on that. But beyond that, there are a number of ways in which particular nutrients, and the case of today's episode, sugar, impact the way that the brain works, such that we tend to seek out more ticula nutrients. For instance, if we eat sugar, there are two, or at least two mechanisms by which we will crave more sugar.

I think most people aware of that experience, but today i'm going to explain exactly how that works, but also that when we can just sugar, IT has a bunch of different effects on the way that our neural circuits work that can allow us to be more or less focused, more or less agitated, more or less happy, more or less depressed in some cases. So today, as we explore this thing we're calling sugar, we are going to explore that mainly in the context of the nervous system, but also in the context that have the nervous system regulates many, many functions and behaviors that are important to all of you. Your ability to think, your ability exercise, your ability gain weight, lose weight, whatever your goals might happen to be.

Sugar plays a critical role in achieving those goals. And in some cases, if you're interesting too much at the wrong time, at the wrong forms, sugar can actually impede those goals. In fact, sugar can prevent all the right behaviors from allowing you to achieve the goals that you want.

So today we are going to place sugar into its proper context. The way I wanted start off by doing that is to tell you a little bit of what happens when we eat and a little bit of what the brain does to respond to those events. So what happens when we eat? Well, i've done an entire episode on metabolic.

So if you're interested in the full cade of hormonal and neural events that occurs when we eat, please check out that episode. But for sake of today's discussion, let's just take a what I call top counter review of the hormonal response to ingesting food. Now any time we eat that is the consequence of a number of things that happened before we ate.

There's a hormone in our brain body called glen spell G H R E L I N glin is a hormone that increases depending on how long it's been since we ate last. okay. So the longer it's been since we had a meal, grant levels are going to be higher and higher and higher.

And IT essentially makes us hungry by interacting with particular neurons in an area, the brain called the argument nucleus of the hypothetical mas, and some other areas as well, like the lateral hypothalamic. You don't need to know the names of those brain areas, but if you'd like to know them. There they are grown increases IT tends to make us hungry.

And then when we eat, typically what happens is rolling levels go down. So it's a very logical system now when we eat, assuming that we eat carbo hydrate, but even if we just eat some protein and some fat, we will experience a slight, or in some cases, a large rise in blood glue. Cos blood blue coast is simply blood sugar.

And the body and brain, we should say particular the nervous system doesn't function well if blood sugar is too high or too low. So as a consequence, we have another hormone, which is released from the pancras, which is called insulin, which helps regulate the amount of glue cose in the bloodstream. So even if you were to ingest an entire cup and adults cup of pure table sugar, which would send your blood glucose very, very high, assuming that you have a Normal insulin response, that you're not diabetic, that insulin response would help clamp that blue coast level so that he did not cause damage to your brain and body.

Because if blood sugar goes too high to actually toxic to neurons and other cells of your body can kill them off. And neurons of the central nerve system mean in the brain and spinal court, once they are dead, they do not come back. So your biological systems understand this at a biological level, that is, and prevent that death of cells due to hyborian sugar by keeping insuing around in order to clamp blood glucose.

Diabetics, we call them type one diabetes CS who don't make insuing, have to take insulin when they eat, in particular when they eat foods that raise their blood sugar specifically to avoid that neurotoxicity and the other diller's effects of hyborian sugar. okay? So glin is a hormone that goes up the longer it's been since we've eaten, intends to stimulate hunger.

When we eat grilling, suppressed blood glucose typically goes up, especially when we eat a carbo hydrate containing meal. When black blue coast goes up, it's regulated in the body, meaning its peaks in its valleys are more than smooth out. And that glue cos sweared, it's taken away where IT needs to be taken away.

And in certain locations, it's delivered to cells so that those cells can use the glue cose. Now one of the chief organs for glue utilization is the brain. Neurons are tremendous, ly metall ics active, and they're preferred mode of metabolic is glucose metabolic.

Other words, neurons basically run on sugar, which is not to say that you should eat a lot of sugar. As you'll see today, there are states of mind and body for since fasted states in which people report having amen amounts of mental clarity, and their blood lue costs actually quite low. So IT is simply not the case that the more sugar that you adjust, the Better that your brain will function.

But IT is the case that for most people, meaning people who are not on a kidgin ic or very low carbon hyde diet, they're not adapted to low carbon hyper diet, that neurons in their brain and body are using glucose in order to function. That's what allows us neurons to fire electrical potentials that tell we referred to IT firing, meaning sending electrical signals down their life to communicate with other neons. To illustrate just how important glue cose is for brain function, i'd like to describe a study that just recently came out that sits on a long history of similar studies, but the one that just came out is particularly interesting.

Now I want to point out that unless I say otherwise, i'm going to refer to typical diets, meaning I have to believe that most people out there are ingesting some starter carbon hydrate. I do realize their people following very low carbon hydrates diet, moderately carbo hydroid diets. I even know there's some folks out there here on the so called carnivore diet.

They only meet an organs, maybe a little fruit. But i'm going to assume that the vast majority of people listening in just proteins and carbo hydrates. So unless I say key to janek, where I emphasize the key tos itself, which I will, i'm referring to kind of typical diet twor.

People are consuming fats, proteins to n carbo hydrate. I count myself as one such individual at some point. I might try the kind of voda, who knows? I might try a pure vegan diet, who knows.

But for my entire life, i'm until now, and forty six years old, I been a proud of of war being. I've tried the high quality as much as I can, unprocessed. oops.

I try and really avoid highly processed oos. But I do eat from those three macor nutrient groups. Proteins cover hera's and facts, and I assume that most of you do as well. The study, i'd like to emphasize, recorded from neurons, nerve cells in the brain, in particular in the part of the brain that responds to visual images, so called visual cortex. And neurons in the visual cortex are beautifully tuned, as we say, to particular features of what we see.

The primary example of this, the kind of classic example, is if you put a little electrode next to the erwin, your visual cortex, or if we put you into an f fmri skinner machine, which can detect nerve activity. And I were to show you a bunch of um just little lines, you know, bars of light that could be dark, bars of light that could be light, bars of light on a screen in front of you. So some would be vertical, some will be horizontal, some will be at forty five degrees.

What we would see is that some neurons respond best, meaning they fire a lot of electrical activity to vertical lines. Other ones respond to horizon onto lines, and others were respond to forty five degree lines. And this so called orientation tuning, meaning, because the orientation online is a cardinal classic feature of the way that your visual system is built and everything that you see, whether it's a face or a dog or a cat or a landscape, is built up from these very simple neuron responses.

In other words, when you look at a face, there are neurons deep in the brain that respond to faces. But the only reason that those neurons can respond to those faces is because they receive signals from neurons, individual cortex, some of which respond to vertical lines, some of which respond to hormonal lines, and some which respond to forty five degree lines. And all of those are built up in what we call a hierarchical representation, was just fancy language.

For those are the building blocks by which you see a face and you recognize a face. It's really an amazing phenomenon that happens very, very fast. You never noticed that you're doing this, but everything is built up from these fundamental orientation tuned neurons.

Now orientation to neurons are so fundamental that they are the building blocks by which you make up all other things that you see. It's the way you read. It's the way that you recognize faces, as I mention, and everything else. Experimentally, it's quite straight forward to measure how sharply tuned one of these neons is.

In other words, if I were to show you a vertical line and find a neuron in your brain that responds to vertical lines, I could also ask whether not that neuron fires any electrical ectivity in response to line that's not quite vertical, maybe just ten degrees off vertical, or twenty degrees or thirty degrees. And what I eventually would find is that that neon was orientation tune over a particular range of angles. It's not only going to respond to vertical lines, is also going to respond to lines that are about ten degrees of vertical in either side, but probably not much more, maybe twenty, but usually it's going to be anywhere from vertical to just tilt IT slightly.

Okay, in the recent experiment that was publishing the journal neuron, so press journal, excEllent journal, the authors asked a really interesting question. They asked whether or not the sharpness of tuning, the precision of orientation tuning of these neurons is dependent on blood glucose level. So just to cut to the chase to give you the answer, what they found is that when subjects are well fed, neurons that responded vertical responded very strongly to vertical, but not very much at all to other angles of what we call stimuli.

Deadlines that are ten degrees are twenty degrees off. If they looked at her on that were primarily tuned, right, that preferred horriston tal lines, they found the same thing. okay? So IT wasn't something unique to vertical lines.

What they basically found was the sharpening. The precision of tuning of neurons in the brain was best when subjects were fed, and conversely, when subjects were fasted. The orientation tuning of these neurons became much broader.

What I meant was that a neuron that Normally would only respond to vertical now responded to other angles of lines as well. You might say, well, that's great, right? These reasons that at one point can only do one thing or now tune to other things.

But it's not so great because what that means is that in the fasted state, your perception of the outside world is actually distorted. It's blurred. It's not as precise as IT is when your feet. And when I say fed, what I really mean is when glue costs available to neurons. Now, for some of you, maybe many of you, and including myself, intermit and fasting, or some variant there of, is actually a state that I like IT allows me to focus for insinuation.

I mentioned before and even earlier in this podcast, I tend to eat my first meal sometime around eleven, and then I generally at my last meal sometime around eight P M, plus or minus an hour on either side. I'm not super strict about an occasional wake up really hungry and i'll eat something before eleven. I am, i'm not superstring t about this internet fasting thing IT just seems to be how my appetite works best.

Given my schedule at sea in the morning, I tend to be most focused, and I always associated that with the fact that I was fasted. I just water in some caffeine about ninety minutes after waking up. I drink my caffeine, but I hydrate from the time I get up.

But and I know a lot of other people have had the experience of being fasted and finally have a lot of mental clarity. When you are in a fasted state, typically you are going to use fuels that are available to the neurons based on your intake of food the day before. Maybe it's you're using some like a gen, maybe you're using some fat, maybe are using some blood sugar that derived from other storage sites in the body.

You don't actually use fat as a fuel source for neurons under typical conditions, but there are ways in which proteins and fats and like genetech are converted into fuel that neurons can use. What's interesting about this study is that the study says that when well fed, meaning when blood glue cos sugar is at a properly elevated level in the bloodstream, IT can be delivered to the brain a way that allows neurons to work best, which is really all just to underscore the point that I made earlier, which is that your nervous system is extremely metabolite demanding, and IT loves glue cos neuron to love glue cos. So the takeaway from the study is not that you should avoid fasting.

The take away from the study is that there are all elements of the fasted state, in particular the elevations, and things like een efron and nor ean f an, also called a journey and nor journey, that can give us this kind of clarity of mind that many people are pursuing when they fast. That's kind of one of the reasons a lot of people fast, they like the way that they feel mentally, physically. But I think it's only fair to point out that glue coast is the preferred source of fuel for the brain.

And the study that I mention is one of many studies that have explored how nutritional status or blood luco status in the brain body in influence, neuronal tuning and neuro nal function. And IT really points to the fact that ultimately, your brain as an organ is a glucose consuming machine. Now, when you eat a food, that food is broken down, and if IT contains carbon hydrates tes is going to be converted into glucose, and that glucose can't get directly into the brain as a fuel source.

IT actually has to be Carried across the so called blood brain barrier, the bbb and the actual metabolic of glue cose. And the delivery of the blue coast to the neurons is Carried out by a different cell type. And it's a cell type that you should all know about because it's the most abundant cell type in your brain and maybe even in your entire nervous system.

And that's the so called astra de asta. Cites are one of several types of glia that where glia means glue, but many people have taken that name, ga glue, to think that, oh, the only thing that the exercise are doing, you're just kind of holding things together. Actually, the exercise are involved in delivering glucose to the neurons.

They are critically involved in shaping your neural function and brain plasticity, the brains ability to change in response to experience. So these exercise are like the little waiters and waitresses bringing glue coast to the neurons. And the neurons are going to do the heavy lifting that's involved in perception and behavior and action.

So if prior to this episode, you didn't already realize that glucose, blood sugar is vital to the function of your brain and other neurons of your nervous system, now, you know, and for those of you that have experienced the increase in, so clarity that comes after a properly timed, properly composed meaning has the right macer nutrients and the right ratios and the properly sized meal, well then now you have justification for eating something in in as a way to improve the way that your brain works. IT turns out that your brain is going to work best when it's got glucose available, whether you like to fast or not. That's just the reality of things.

The same thing is also true for the neurons in your body, the way that you are able to move the limbs of your body, the way you are able to perform exercise or movement of any kind, for that matter, is because neurons, called motor neurons, send electrical potentials to the muscle fibers. They release a newer transmitter called the seat to Colin, which causes contraction of the muscle fibers and allows you to move your limbs. Those neurons are also very metabolite demanding, especially when you're doing demanding types of physical work.

And that could be cycling or running or weight lifting or yoga, whatever IT may be. Those neurons require a ton of glucose. If you've ever had the experience of having to think very hard about how you're generating a movement or force yourself to continue to endure in a given exercise, you might have thought, oh, you know, i'm running out of fuel.

That's why i'm getting tired. It's hard to do. That's actually the case sometimes, but that's not always the case.

One of the reasons that IT feels like work is because you are so called upper motor neurons, the one that controlled the lower motor neurons in your sports, which control your muscles. They have to be very metall ics active. It's one thing to engage in a reflective movement. We are just walking around if you're running continuously. But when you suddenly have to focus on what you're doing and you have to generate specific patterns of motor movement, well, that feels demanding because one IT increases the release of a journal in in your brain and body, which makes you feel a little bit agitated, more alert, but also deliberate thought. Deliberately controlling the way that your brain in body is moving requires more glucose, sub take more energy in those very neurons.

And this is also why, after doing a long bout of exercise, you might be, but also, if you do a about a skill learning of any kind or if you've been reading and thinking about what you're reading or if you had a intense conversation with somebody are really forcing yourself to listen and hopefully you're listening to you too and you're really trying to pass what they're saying and maybe are doing that right now and you're trying to really track something that's work. And that work requires glucose subset by neurons, both in the brain and in your body. Now that we've established, glucose is the preferred source of fuel for the neurotic system.

I like to concentrate on a few of the other types of sugars that we ingest on a common basis, and the impact that those have on brain function and body function, i'd pretty fully like to focus on fractus frick tos, of course, is found in fruit, is also found in the infamous high fractus corn sr, which we will talk about today. It's worth pointing out that the concentrations of friction s in fruit is quite low compared to the concentrations of fractus in hydro to concert. Hydro concert is approximately fifty percent for actos, which turns out to be enormously high percentage of anything really, especially when we contrast that to the concentrations of ricos in fruit, fruits have other types of sugars in them as well.

You know the sucrose content of most fruit and fruit juices as low um although there are some fruits like you know mellons, peaches, pineapples and so so forth that contain you know little less than ten percent or so of success um things like mangoes can have a lot of sucrose. But typically the amount of fruit s fruit toast, I think, is the proper pronunciation that people are always correcting me frc toast is anywhere from one percent to about ten percent, right? It's really gonna very, quite a bit.

And many of you have probably heard of the so called gay simic index, which is a basically a measure of how fast blood sugar rises after eating particular foods that we're going to set a side. The glasses make index. For now we will come back to IT.

IT has some relationship to the concentrations of friction s in fruit. But the point i'd like to make is that fructose, as a sugar, is handled very differently in the body. Then is glue cos. But I also want to emphasize that because the percentage of friction s in fruit is rather low, especially compared to high fractus corn serve, many people have demonized frick tos, saying that fractus makes you fat, or that fruit makes you fat. If you look at the data, that's not really the case.

The fact of the matter is that the concentrations of fotos in fruit are so low that unless someone is consuming a lot of fruit, or they are consuming a lot of fruit on the backdrop of a highly process, died or died, that has a lot of other stuff that they might not want to be interesting. You can't really say that fritos is fattening. I don't really think that there is any basis for saying that fractus itself is bad.

Now high fractus corn is a different issue, and too much consumption of anything but photos included with that, that comes fruit or otherwise can be a problem for the ways that IT impacts the neural circuits that process sugar, not just glucose, but fructose. And so will illustrate those neutral circuits in a bit. And you will become very clear to all of you, regardless of where that I have a background in biology, metabolic nutrition and otherwise, why ingesting very high concentrations of frick tos is not going to be a good thing for the way that your brain functions.

One of the key distinctions between glucose in frick tos is that fritos most likely cannot directly access the brain. IT actually needs to be converted into glue cose in the liver. And the way that conversion occurs feeds back to a set of horn mones and neural pathways that we talked about earlier, which have a lot to do with appetite.

And you just summarized what is now a lot of very solid data. Fructose, and specifically fruit s, has the ability to reduce certain hormones and peptides in our body, whose main job is to suppress glin, as you recall, gillis, and hormones that increases the longer been since we've eaten. And Green makes us hungry by stimulating particular neurons in hypothalamus.

IT actually makes us really want to eat, and in particular, really makes us want to eat sugar and fatti foods. Fructose reduces the activity of the hormones that reduce glen. And so the net consequence of that is that fructose increases gilling.

So although I and I think pretty much everyone else there, safe for a few individuals, agrees that calories in, calories out as the undamned tal principle of weight loss, weight maintenance, weight gain, ingesting fructose shifts are hormonal system, and as a consequence, our neural pathways within our brain, the hypotheses to be hungry, regardless of how many calories we've eaten. okay. Now I also want to be absolutely clear.

This does not mean that they are eating an apple or eating a melon or eating a couple of apricots or something is going to make you hypothesi c meaning is going to make you just want to eat meat. That is simply not the case. But if you compare fractus and he compared red glue, cose not only them etablishment renting in the brain and body, but in addition to that, frick tos has this impact of reducing the hormones that reduced hunger hormones and neural circuits.

And so fritos does have this kind of twist in its u m 4 type right or or it's I guess if friction s had a dating profile， this would be a kind of a red flag in uh in that profile. Because fructose itself, well, it's actually a pretty good fuel source in in many ways and it's often package in things like fruits which bring along fiber and vitamins and minerals that I think for many of us are, are things that we should be eating more of. An interesting more of.

IT can suppress the pathways that suppress hunger. And as a consequence, IT can increase hunger. So current recommendations for most people are to eat more fruits and vegetables. But for those of you that are trying to control your hunger, ingesting a lot of frick tos is probably not going na be a good idea.

Certainly interesting from high fractus concert is not going to be good idea because of the enormous percentages of fractus in high fractus concert, fifty percent or sometimes even more. But even from fruit, some people will find that fruit really quenches their appetite. Other people will find that fruit stimulates their appetite.

And I suppose if you're trying to stimulate your appetite than ingesting more fruit might actually the advantage to you. So fruit tos provides a bridge for us between a particular kind of sugar hormone function, in this case, grilling. And the hypothalamic leads us to the next question, which is, what is IT about sugar that makes IT such an attractive thing for us? Why do we like IT so much? And the obvious answer that most people arrive at is IT just taste really, really good.

But that's actually not the way IT works. The rewarding properties, as we say, of sugar, whether they come in the form of sucrose or fritos or friends, that increase glucose to A A very high level, actually is not just related to the taste of the foods that produce that elevation in glucose, sucrose or fotos IT is in part. But that only part of the story and the rest of the story, once you understand IT can actually place you in a position to much Better control your sugar intake of all kinds, but also your food in taking ways that can allow you to make much Better choices about the food to you ingest.

And actually at this point, I should probably give a confession said today, and i'll say IT again, and i've said IT on previous podcast, I don't have much of a sweet tooth and I dee, that's true and I can kind of pass on chocolate or ice cream or things like that. Seems like with the success of year, sweet things are less and and less appealing to me. Of course, savery foods um anything that uh is really uh fatty, salty savery h those don't last long in my presence but I would say I don't really like sweet things so much and I don't I like sweet people but I don't tend to like sweet foods um which is true, but there's probably one exception.

And that's mangoes. And turns out that mangoes have the highest percentage of sugar in them, in particular fotos as well as other forms of of sugars. So what I do because I love mango so much as I will have mangoes probably twice a week, but i'll have them after some sort of resistance training or hard run or something like that.

Because this is the case that after you exercise hard, in particular exercise, that is of the high intensity variety that your body is more efficient at using circulating blood sugar, it's able to store that or use that for fuel. And so the what I typically do is just take the mango, actually eat the peals too. I know there are problem, some people going to courage when they hear that, I find them delicious, and I just bite in to those things like apples.

I don't eat the pits, however. So now I want to take us on a journey into the nervous system to explain the pathways in the brain and body that regulate our appetite for sugar. Keep in mind, when I already told you before, which is that when we and just foods, they're broken down into various components and blue coast is going to be shuttle to the brain, and of course, the other neurons in our spaces d and elsewhere and to our muscles that that are in order for all of those cells and organs and tissues to be able to function.

The fact that so many cells and organs and tissues require glucose in order to function has LED to a situation where you have dedicated neural machinery pieces of your brain that are almost entirely, if not entirely, devoted to seeking out of sugar or foods that contain sugars, and to make sure that you not only seek those out, but you know where those foods are and that you just more and more and more of them. And there are two main ways that these neural circuits work. In fact, we can say that there are two neural circuits entirely that work in parallel, and this is a common theme throughout the server system, and that's parallel pathways.

Parallel pathways are the ways that you can distinguish light from dark. Parallel pathways are the ways that you can distinguish high pitch sounds from low pitch sounds. Parallel pathways are the ways that you can flex your muscles versus extend your muscles.

For instance, if you move your rist closer to your shoulder, you're flexing your bay step and you're actually inhibiting you're actually preventing the action of your try step. If you move your your risk away from your shoulder, you are essentially using your extensor your try step, and you are inhibiting the activity of your bye p. So for every function in your body that you might think is controlled by one brain area, one neural circuit, almost always there are two or more so called parallel pathways that ensure that that particular behavior happens.

Now, in the case of sugar consumption, the two parallel pathways involve one pathway related to the actual taste and the perception of sweet case that lead not just you, but every animal that were aware of to seek more sweet containing foods. The other parallel pathway is related to the new tractive component of sweet foods, meaning the degree to which a given food will raise blood glue. Cos, I want to repeat, that one pathway in your brain and body is devoted to getting you to seek out sweet tasting things that you perceive as sweet.

And another parallel pathway is devoted to getting you to seek out foods that lead to increases in blood glue. Cos, IT just so happens that the foods that lead to big increases in blood locos typically are associated with that sweet taste. Now this is distinctly different than the neural pathways that control seeking of service foods, or salty foods, or spicy foods, for that matter, or bitter foods.

The sweet pathway is what we would call hardwired to exist, as far as we know in every memo that even exist in fruit flies. Hence fruit fly. Basically, getting sweet stuff into the body might seem like IT has a lot to do with the taste, but IT has just as much to do with the nutritive components that sweet tasting foods Carry in the fact that your nervous system and so many cells in your brain and body run on glue.

Cos, if you were call earlier, I said, even if you in just frick tos, friction s can be converted into glucose in the liver. And I mention, of course, that fractus may actually work directly on the brain. That's still unclear for humans. You know, the jury still out on that, you will see.

But the fundamental thing to understand here is that when you think you want a piece of chocolate, or you think you want a piece of cake, or you're craving something sweet, you are both craving the taste, and your neurons are literally craving the nutrition tive components that arrive with with that taste. And simply by understanding that can allow you to circumvent. Some of the sugar cravings that you might otherwise be a complete hopeless victim to.

Also in this episode, I will talk about ways that you can sort of undermine or short circuit these circuits, if you will, in order to reduce sugar cravings on a regular basis, if that's your goal. Two parallel pathways. One of the parallel pathways has to do with conscious perception.

So animals of all kind's, my rat and humans will prefer sugar y taste to non sugar y taste. When we eat something that takes sweet, we register that sweet taste by way of sweet receptors, literally little ports or portals of neurons on our tongue in on our pilot. Lot of people don't realize this, but there are a lot of taste receptors on the soft palate and around the mouse, on the sides of the mouse, where you're actually tasting things not just with your tongue, but with your entire mouth and your polite.

So when you and just something sweet, very quickly, their signal sent from those neurons in your mouth to brain areas that cause you to seek out, or at least pay attention to, the source and the abundance of those sweet things, they literally change your perception. In fact, there are beautiful neuroimaging studies that show that when people in just a sugary drink, their perception of images of friends change very much to make those foods appear more appetising. And not just foods that contained sugar, results of these studies do show that there's an increase, for instance, in the a perception of detail and images of ice cream.

After you in just a sweet drink or even put like a hard Candy into your mouth, IT will make you seek out sugar things more IT will make sugar things look more appetising, but also other foods more appetising. So I think it's important that people recognize that fact that when you have a sweet taste in your mouth, or when you tasted something sweet within your mouth, I should say your perception of food has immediately shifted. These are fascinated pathways that will get into some of the brain structures in a moment, but these are fascinated pathways that shift your entire self toward seeking more sugary stuff and more food generally.

no. Does that mean that you should never just anything sweet? No, certainly, i'm not saying that I don't want us to decide for themselves what the appropriate amount of sugar intake is, but I find IT remarkable when people say, oh, you know, I need to get my sugar fix or I need to have my chocolate, I need to have a little bit of something, just kind of take care of that sugar appetite.

Because in taking care of that sugar appetite, maybe for the very disciplined of view, you can just have that one piece of chocolate. It's great, and you can relish in IT. But IT does shift the way that you perceive other foods as well.

And the way IT does that is through our probably if you're living in this podcast now, old friend, but incredible nurse dulce, or dope doping, is a molecule that is released from several places in the brain. There is a so called me olympic reward pathway, which is a whole set of places in the brain or circuits designed to get us motivated and craving and in pursuit of things. And then, of course, there are areas of the brain that are involved in movement that are linked up with those areas involved in motivation.

That makes perfect sense. Why would you have a brain area involved in motivation if you could actually do something with that motivation? So the way that your brain is designed is when there's an increase in dopamine e in the musical limited reward pathway, there are signal, the area of the brain called the striatum, where going to spend a little bit of time today in the stride ATM, it's got a dorsal panting in upper part, a ventures partner, which he means lower part.

And the dobin sent to those areas, places, places are, excuse me, into modes of action to pursue particular things. Sugar or sweet taste, I should say, to be more specific, have an incredibly potent ability to activate doping release within the mysol mic reward pathway. This has been shown over and over and over again in animal models and in humans.

This is especially true, I should mention, through the injection of sweet liquids. Now this becomes a very important point to us a little later on, when we talk about the proliferation of sodas and sweet drinks, and there are even say, non sugar or diet sodas, we're going to get into that a little bit later, the perhaps one of the most third rail topics in nutrition. But when we adjust something sweet, the perception of that sweet taste increases dopy in the misery's c reward pathways, which that are conveyed to pathways for motor or behavior, and in general, places into moths of focused action toward getting more of whatever was sweet.

Again, for those of you that are very disciplined, you can probably eat that one piece of chocolate and be just fine. But if you understand the way that dopamine works, what you'll realize is that when this dopamine pathway is triggered, IT tends to create not this sensation or the perception of safety, of feeling like something is enough, but rather to produce the sensation of wanting more. As described in the episode that I hosted with my phenomenal colleague from canford school of micon doctor on a empt y, she's an expert on addiction in dopamine e pathways.

The dopamine circuits of the brain have what we call a pleasure pain baLance. And there are periphrases what doctor analyst key, has said and has written about in her beautiful book, document nation. If you haven't read that book, I highly recommend IT.

Whether or not you have issues with addiction or you know, people that do or you don't, it's an incredibly important read, especially if you're interested understanding motivated behaviors and ways to channel your behaviors in life toward healthy motivates behaviors and make sure that you avoid some of the common pitfalls that people fall into, not a addiction, but things like over use of social media or a wasting time in general. It's a phenomenal book in that book end. Of course, within research articles, you will find evidence of this so called pleasure pain baLance that exist within our diploma in circuits.

Nobody has dopamine circuits that allow them to escape this pleasure pain belt. And the way this works is that any time that we engage in a behavior, or we adjust something that increases our levels of dupine, there is a subsequent increase in the neural circuits that control our sense of frustration, pain and lack. And you can actually notice this phenomenon if, for instances, somebody who really likes chocolate, or you really like something else, pay attention to the way that you experience indulging in that thing.

If you eat that piece of chocolate and you really focus on saverin IT amazing taste, you'll notice that IT provides some quenching of your desire for what's a sweet stuff, or chocolate or both. But right, as you stop experiencing that, right, is that chocolate intake tapers off as you swallow IT down your throat, or you just pauses for second affords, what you'll notice is that your brain and body actually orient toward wanting more. And that wanting of more is really the action of the neural circuits that underly pain and are pushing your domine levels back down.

And when these circuits go right, or I should say, when people fail to control themselves within the context of that pleasure pain, baLance the typical behaviors to reach for yet another chocolate, or to then look for something that will quent that desire and get dopamine e levels back up. Now the way these pleasure pain circuits work is really diabolical, because IT turns out that we're you to take another piece of chocolate. Yes, your dopy levels would go back up, but not to the same extent that they did the first bite of chocolate that you had.

In fact, we can say that the longer it's been since you've indulged in something that you really enjoy or would like, the greater the dopa amine you will experience when you finally engage in that behavior or indulge that thing and just that thing. And the greater the dopamine an increase, the greater the subsequent action of those pain circuits. So this puts you on a very complicated sea saw.

It's a very warmly precarious state to be in, which is not to say you shouldn't have a piece of chocolate, is just to say that the sweet taste of sweet things, particular things that we crave very much, and we wait and wait, wait, and then we allow ourselves to indulge those triggered changes in our neurochemistry, our neural circuits that places in a very vulnerable place to either want more and more of that thing, or to seek about other ways to fill that kind of emptiness that we feel her, that gap. Like I would love more, but i'm not going allow myself more. Now again, i'm not saying that you shouldn't have pleasurable things.

I mean, molecule dopamine exists for a reason. It's the, Frankly, because of its involvement in sexy reproduction. It's the reason we're all here in the first place, because last time I ject the only way any of us got here was one way, another permet egg.

And there was conception. I still believe there are no exceptions to that then i'm aware of anyways. That is a process where I should say the events leading up to that process typically involved dopamine e in one way another.

There are exceptions to that too. But you get the idea these dopamine pathways are not evil, they're not bad. But once you understand the way they work, you can leverage them to your advantage as opposed to them leveraging you to their advantage.

Okay, so when you and just something sweet, you perceive that sweet taste in a cascade sues within your brain that makes you want more of the sweet. That's the conscious pathway for sugar perception, for sweet perception. Now there is the second pathway.

The second pathway is what's called the post injustice reinforcing properties of sugar, which is really just a fancy nerd speak way of saying the events that happen within within your stomach and below your conscious detection that are also driving you to seek out sweet tasting things independent of their taste and foods, the increased blood blue coast independent of their taste. In order to illustrate the immense power of these subconscious circuits for sugar seeking, i'd like to describe an experiment. And this is just one experiment of many of dozens or more experiments done in animal models and humans, which essentially illustrate the same thing.

And as I described this experiment, I think you'll come to understand the power of these circuits. I'll provide a link to this study uh in the caption the first author s freeman um the paper with polish in frontiers in bioscience but there are many others um papers in nature neuroscience papers in neuron sell press journals instead of many, many jerks, many, many papers if subjects are given the choice of drinking plain water or a sweet tasting fluid, their preference for the sweet taste fluid is much, much higher. Sweet things taste Better than plain water, at least for most people and certainly for animals now.

If, for instance, you take an animal which completely lacks sweet receptors, and you can do this through some h molecular genetic tools and gym nama sticks in the laboratory, we call these knockout mice, where you can knock out of particular recept for sweet days, you can confirm that there's no perception of sweet things or at least no preference or sweet things um in those animals and humans you can numb the outs there other pharmacologic ways that you can eliminate sweet receptors in the mouth and by doing that you people will tell you, no, I can't taste anything sweet. It's just there's you could give them a ice cream, you could give them pure sucrose, you give them table sugar and they wouldn't able to perceive a sweet. If you eliminate the perception of sweet taste in the month, then you offer people or laboratory animals water versus some sugar containing solution that you eliminate the preference for the, for the sugar y solution, which tells us that the perception of sweat is important for the, for the preference for sweet tasting drink.

This is also true for sweet tasting foods. I should mention, however, in both animal models and in humans, after about fifteen minutes, subject start preferring the sugary water, even though they can't taste that IT is sweeter. Okay, so to repeat that, if you eliminate the ability to sense sweet, to perceive sweetness in foods, then you eliminate the preference for sweet beverages or sweet foods.

So that's not surprising. But if you wait about fifteen minutes, the preference for the sweet beverage of the sweet food comes back. Now that doesn't mean that they can perceive the sweetness. In fact, you, the way these experiments are done is very clever. You offer people various cups of different things or different food items, and then you just look at what they eat more of, or what they prefer eat more of.

So this experiment is so crucial, because what IT says is that the preference for sugar containing foods is in part due to the sweetness of those foods, but in part due to something else. And there's something else is what we call the post injustice effect. And as I mentioned before, I took about fifteen minutes, and you've actually experiences this, whether you realize or not, this phenomenon on a post congestive rewarding properties of sweet foods, meaning what happens in your body when you adjust something that increases your blood.

Lue cose very much has no doubt controlled you from the inside, below your awareness. This was happening to you, and you didn't realize IT. Here's how outworks.

We all have neurons within our gut. These neurons have a name. They are called neuro pod cells. Neuropace cells were famously discovered by professor doctor jago horcoff at due university. And these cells respond to, among other things, to the presence of sugar within the gut.

So when we ingest a sugar y food or drink, or we ingest a food or drink, that simply contains four to sucrose, glucose or some other form of sugar that later through metabolic, will be converted into glue, cose the europol cells are able to register the presence of those sweet or glucose stimulating foods. And in response to that, send electrical signals, because electrical signals for the way in neons communicate up to the brain via s so called vegas nerve, the veggie st. Nerve, of course, being a nerve pathway famous for its role in relaxation.

That's kind of the the assumption out there is always involved in relaxation. That's not the case involved in a lot of things besides relaxation. But nonetheless, neuroprotective ls send electrical signals through a particular highway within the vegas to the so called noodles gangly en.

This is a cluster. Gangling is just a cluster of neurons, and then the noodles, gangly en, sends on information to the nucleus of the solitary tract. The nucleus of the solitary tracked is an area of the brain that we are going to talk about extensively today is very important for understanding sugar preference.

These europol cells also trigger activation of dopamine pathways within the most olympic reward pathway. In other words, there are signals conveyed from the gut, meaning stomach, and in testers to the brain. Any time we just sweet foods, but IT has nothing to do with our perception of them being sweet as everything to do with the fact that sweetness of food is almost always correlated within a to increase blood glue cos.

And the net effect of this is a parallel pathway by which doping is increased further. Now, the experiment that I described before of animals or humans ingesting something that contained sugar, but not being able to perceive its sweet tss, and yet, after a period of time, still preferring that food or drink to non sugar, gaining footer drinks, even though they can't distinguish their taste, is dependent on these neuroprotective ls and related pathways. What this means for you is that any time you eat something sweet, that substance is actually causing your gut, your stomach, in your, in testing where, to be more precise, I should say that substance is food.

Substance is causing the neurology cells in your stomach and in testers to send a parallel set of signals up to your brain saying, eat more of that, or simply eat more, eat more, eat more, and preferably eat more sweet foods. So we've all heard of hidden sugars, meaning the sugars that manufacturer have put into foods and disguise them with other flavors. I talk about this in the episode on salt, using salt to mask the taste of sweetness, that people in just more sugar.

That is not an accident, that hidden sugars are often hidden with salt or with other flavors. It's done so that people will, meaning you or me will want to injust more of a particular food independent of how sweet that food taste. And in fact, some crackers, for instance, chips, for instance, you might think, oh, well, you know, chips, they're not sweet.

They're salty and savery. And I again, I mention I love salty, a savery foods, including certain food that love kettle chips. For instances, try not to walk by them in the yurt y store. I usually have to eat one backwell. I'm in the store and then another later.

The savery foods are often laid in with these hidden sugars that we can't register sweetness but trigger the neurology cells, which then further trigger dope, I mean, which make us want more of them. Now we may be able to resisting more of them, but IT makes us crave more food in general. Now we will talk about ways to regulate this pathway, sort of intervene in this subconscious pathway.

But for now, i'm hoping that just the understanding that we all have this path, way this is hardwired into our body, could potentially allow people to Better understand why is IT that their cravings are so intense that it's not necessarily just about the taste of that food. And when you consider this in concert with the fact that we have this dopamine e pain, pain pleasure baLance, excuse me, that I referred red too earlier, you start to realize that there are multiple mechanisms hardwired into us that make IT especially hard to not eat the sweet thing or to not eat the food that we're craving. And indeed, that's the case.

We have two major accelerators, is like a car with two accelerators. And we will talk about the bricks, but two ways that really get us into forward motion toward pursuing the consumption of sweet foods. Now if he doesn't always seem diablo enough, that sweet things that we perceive a sweet make us want to eat more, those because of dopamine, and then send us down this pain pleasure pathway.

I mentioned earlier in the fact that we have this subconscious circuit coming from the europol cells in our gut that are registered in the presence of sugar or glue cos increasing foods and our gott, and sending those signals to the brain for yet more dopamine pain, pleasure chAllenges. There's a third layer to this whole thing, and that has to do with how sugar is meant, abilities ed in the brain, or I should say, how glue cos is used without getting into too much detail, some of the more beautiful studies of neural imaging and evaluating which brain areas are active when we eat certain foods were done by doctor din smallers lab at yale university. And in some of our previous work, when SHE was also were end, of course, by other laboratories too.

And they used in approach called positive ona mission tomography. And then others have used pet scanning as it's called positive emission tomography, along with a tool called two d oxy glue cos. Two dioxid glucose is actually involved in the procedure of seeing which brain areas are active when people eat foods or engage in other types of behaviors.

But the way that to d oxy glue cos sometimes shorten two dg. The way that IT works is to block glue cos uptake from neurons and instead bring along with IT, a marker that one can see through imaging. So in other words, a tool for looking at what parts of the brain are active when eating particular foods actually prevents foods such as sugar from allowing glue coast to get into particular neurons.

Now that might seem like a bad situation. You say, well, wait, you trying to understand how sugar works in the brain. And then you block the ability for sugar blue coast to a buying.

Two were be used by these neurons because of the thing that you're using for the experiment. exactly. It's a huge problem. But IT turns out to be a huge problem that LED to a great insight. And the greater insight is this, the preference for sweet tasting foods and liquids is actually blocked by two dioxid glucose.

What that means experimentally, but also in terms of what that means for you and me in the real world, is that there's yet a third parallel pathway that's related to the use of blood sugar, the use of glue coast by neons, that further reinforces our desire to eat more sweet things. And the preference for sweet foods can actually be eliminated through to the oxy glue cos. Now I am definitely don't want people going out and consuming to the oxy glue coast.

This is a laboratory tool. IT is not something that you should be ingesting. So don't go look at up and trying get some there might be other uses for, but that's not the point.

The point is that IT is the sweet taste of sugar y foods. IT is the signals coming from your got, from your digestive track to your brain. And it's the use of the metal ballet consequences of sugary foods that are acting as a three pronged push on your desire to consume more sugary foods.

So this car analogy that used before, where is some weird car, has two accelerators. IT actually has three accelerators. And so with three accelerators all pushing the system hard, we can say, wow, there must be something really special about this pathway.

Indeed, there is. This pathway is the quickest source of fuel for the brain, and the rest of nervous system is the preferred source of fuel for the brain and nervous system. And I realized, as I say, that all that the key to esters are probably going no, actually key tones are the preferred source.

okay? I acknowledge that there are conditions under which you can bring your blood glucose very low. And the reasons to do that. Actually, key tos has been a horrifically successful treatment for a lot of forms of epilepsy, in particular pediatric epilepsy. Many people do derive benefit from key ogen ic diet.

So i'm not knocking head generic diet, but if you were to look at what neurons Normally prefer, meaning in a typical diet regiment, IT would be glue cose. And the fact that fork tos is eventually converted to glue cos, the fact that when we injust sucrose is eventually converted into a fuel that neurons can use that very much in the glucose pathway. What you basically arrive at is the fact that your nervous system is a glucose consuming machine, and you've got at least three pathways of which i've described that are pushing on your brain consciously, instead consciously, to get you to seek and consume more sugar.

Now that all sounds like a pretty depressing picture, at least for those of you, they are trying to reduce your sugar intake. And of course, we can all reduce sugar intake by way of sheer will. We can not have those whose at home we can restrict ourselves from those.

But there are some things that we all can, and perhaps should do in order to regulate these pathways such that we don't feel so controlled by them, but rather that we controlled their output. And of course, they are us and we are them. So this gets into all sorts issues of conscious ness and freewill that I certainly don't want to cover in this episode.

But I think once you understand that these circuits exist, and you understand that their simple substitutions in modifications that one can make to their food intake, that can work within these pathways and even bypass some of these pathways, you started to realize that you have a lot more control over sugar intake and sugar appetite. Then you previously thought, now many of you have ve heard of the so called gaseous c index. The glass simic index is a measure of how quickly blood sugar rises after ingesting particular foods.

And very broadly speaking, we can say that there are logical emc index foods of less than fifty five typically as the measurement, or medium classic c index foods, which go from about fifty five to sixty nine, and then so called high classic c foods, which are above seventy. And of course, there's additional related to classic c load and many more features of the glass simic index. A couple of things to understand about how the classic c index is measured.

And then i'd like to just briefly talk about how the glasses mic index can be leveraged to short circuit some of the neural circuits that would otherwise lead us to crave. And perhaps even in just sugary foods. First of all, measurements of classic induced of food are typically made by having people in just those food in isolation.

And in general, we can say that any time we adjust fiber and or fat lipids along with a particular food IT will reduce the glycemic index of that particular food, either the absolute level of blood glue cos that a particular food causes, or the rate at which that elevation in blood glucose occurs. This is why there are some seemingly paradoxical aspects to sweet stuff in terms of glycemic index. For a since ice cream has a lower licit index provided ice cream that includes fat, which I hope IT would, because that's the good taste.

Ice cream, in my opinion, compared to something like mangoes or table sugar, right? So the classic c index is not something to hold holy in most cases because most people are not interesting food in isolation. And there's actually a lot of argument as to whether not the classic c index is really as um vital as some people claim. There's also the context in which you in just particular food is, as I mentioned earlier, um after I do hard training of any kind, meaning training the auto deplete like you so hard resistance training I actually make IT a point to injust some very sweet high gye mic fu like a mango and also in some starches because i'm trying to replenish language and also trying to Spike my blood you a little bit because that can be advantage in terms of certain strength and hypership free proto calls at sea but most of time i'm avoiding these high classified foods and high sugar foods. I should point that out now.

Why am I telling you about the clastic index? Well, if we zoom out and take our perspective on all of this discussion about the classic index through the lens of the nervous system, and we remind ourselves that neurons prefer glue coast for energy, and that all sweet things, or things that we perceive a sweet, but also sweet things that are injured ted and registered by those neuro pod cells in our gut, trigger the release of dopa mine and trigger these neural circuits to make us want to eat more of these foods, what we start to realize is that a sharp rise in blood lue cose, or a very high degree of elevation in blood, is going to be a much more potent signal. Then will a more motorized blood e cose or a slower rise in blood blue cose? So if we think about the analogy of three accelerators, meaning three parallel neural circuits, all essentially there to get us to seek out and consume more sweet tasting and sugary foods, well then the glass simic index is sort of our measures of how hard we are pushing down or how fast we are pushing down on those three accelerators.

And so those of you that are trying to reduce sugar intake, and you want to do that through an understanding of how these neural circuits work, and you want to short circuit some of the dopamine release that caused by ingesting sugar y foods, IT can be advantages to injust sweet foods, either alone or in combination with foods that reduce class simic index or reduce class simic load. So that might mean making different food choices. So paying attention to sweet tasting foods that can satisfy sugar cravings but do not have a steep or, I should say, do not cause as stearic on blood sugar or IT could mean consuming other foods along with sweet foods in order to reduce the glasses mic index and thereby slow or blunt the release of doping, you might think, well, why would I want to do that?

I want the maximum dopamine output in response to a given sweet food. I don't just want level ten. I want the level one hundred output of doping. But you really don't.

Because of the pleasure pain baLance that dopamine causes, and in fact, we consider some of the non food substances that really pushed hard on these dopamine pathways, we can come up with a somewhat sinister, but nonetheless appropriate analogy. The drug, cocaine, causes very robust pot increases in dopamine within the brain, and typically causes people to want to in just more cocaine because of those sharp increases in dopy. But within the category of the drug cocaine, they're various modes, congestion.

Some people inherit, some people will inject introverts ously, some people will smoke IT. And those different forms of taking cocaine actually impact the dopamine e circuits differently. And IT turns out that crack cocaine, the smoker form of cocaine rock, increases dopamine to a very hyder's, but also very, very quickly. And IT is the sharp rise in dopamine over time, not so much the absolute level of dopamine that makes crack cocaine so absolutely addictive. So sometimes you will hear sugar is like crack.

Well, and that's getting a little extreme because even though I don't think the measurements have been done in the same experiment, I think it's reasonable to think that the absolute level of dopamine caused by ingesting sugar, least for most people, is not going to be as high as the absolute level of document caused by smoking crack. Course, IT goes without saying, please don't do cocaine in any form, by the way, IT is appropriate to say that the rate of dopamine increase over time has a profound effect on how people will and if people will go on to want to pursue more of what cause that increase in dopamine. E, so what i'm basically saying is, if you are going to injust sweet foods in order to satisfy a sweet craving, ingesting sweet foods for which the classroom c index is lower, or in which you've adjusted those glasses mic index food through the coin, justice of fiber or maybe fat might be beneficial.

So is this justification for putting peanut button on that piece of chocolate or for having a bull of ice cream along with the mango that you're craving? In some sense? yes.

However, there's also the issue of how sweet and how delicious something taste. Highly palatable foods, absolutely delicious foods, trigger that one neural circuit, that one accelerator that we're talking about in terms of our analogy of three accelerators. And the more delicious something taste within our mouth, the further increase in dopamine.

So if you really wanted to adjust your sugar cravings, and you really still want to just some sugar foods, you probably be Better off combining fiber with that sugary or sweet food. Now I do realize that it's somewhat unusual, and you probably get some strange stairs if you decided to consume broccoli, for instance, along with your chocolate, or with another dessert that would otherwise cause a steep increase in blood sugar in has a high classic and desk. But none's, if your goal is to blunt your sugar cravings, what you really need to do is blunt that dopamine an increase.

So what really talking about here is trying to reduce the dopamine signal that is the consequence of ingesting sweet friends. And we're talking about doing that through these different parallel, avoid not just by preventing sweet taste, but also by preventing the post digestive effects of sweet food. Ds, and of course, the backdrop to all of this is that most of us, again, most of us, not all, that should probably be interesting.

Fewer refined sugars. Certainly there are exceptions to that. But I think the bulk of data point to the fact that testing these highly palatable, certainly highly palatable, highly processed oos or foods that contain a lot of high friction s corn serb, can be really dillinger's to our health, especially in kids.

And i'm not going to sign off a bunch of statistics you've all heard them before that you know, for hundreds of years we adjusted, you know, the equivalent of a few cups or pounds of sugar per year. And you know, now people are adJusting hundreds of pounds of sugar per year. The major culprit always seems to be sugary drinks, meaning soft drinks.

And I think indeed, that's the case. I do want to a point out the incredible work of doctor Robert tic, who's pediatric and honored gist at university, california. Cisco, who was really early in the game of a voicing the dangers of so called hidden sugars and highly processed oos.

The other people, of course, not talking about this. His laboratory has done important work showing for instinct that if high fractus corn syrup, or even just fractus is replaced with glue cos, even if the same number of calories is injured, ted, that there are important, meaning significant reductions in type two diabetes. Some of the metal bolic syndromes associated with high for current servant on and on and on.

And of course, there are other culprits in type 2 diabetes。 There are other factors that are going to lead to obesity. But I think that work from lustig and others has really illustrated that we should all be trying to reduce our intake of highly refined sugars in hydro OS corn serve and certainly trying to reduce our intake of very sugar y drinks, not just soft drink, but also fruit ices that contain a lot of sugar.

Now even for the people that are a healthy weight and who don't have metabolite syndromes, there may be an additional reason to not want to ingest very sweet foods and how to refined sugars. And this has to do with a new and emerging area of nutrition neuroscience. And I want to point out that these are new data, right? So it's not a lock.

The double blind palacio control studies in large populations have not been finished. So I want to I want to make sure that, that's clear. But I also want to make clear what some of the really exciting data coming from dana, smaller b at yl and from other laboratories are showing.

And this has to do with what's called condition taste preference, using a kind of pavlovian paradise. What they do is they have people. And these studies were done in people in just multiple tran, which increases blood blue. Cose doesn't have much flavor. But even if IT does have a little bit of subtlety lavoro, the multidirectional is closed by some other flavor.

And by closing IT without other flavor or pairing IT with that other flavor, what they find is that over time, because the multi decker in increases blood blue cose and they're ingesting a particular flavor along with that multi dex trine, they can then remove the multi destron and the flavor will induce an increase in insuing. The increase in insuing, of course, is the consequence of the fact that anytime there's arising blood glucose, provided the person is in diabetic, there's a parallel increase in instant. Now this is very interesting because what IT says is, well, at the first past, IT says that we are a very pavlovian in terms of our physical, logical responses to foods and particularly flavors come to be associated with particular patterns of blood glucose increase, and hence, patterns of instant increase.

Because, of course, insulin manages glucose in the bloodstream. As I mentioned earlier, this also has implications for understanding things like artificial sweeteners. And here I want to highlight that this is still very controversial. Work needs more data, but none less. I like to share IT with use for consideration.

The small laboratories has done studies in humans, both in adults and in children, showing that if the flavor of artificial sweeteners is paired with multiple tran and then the multi tran is removed, that the artificial sweetener taste itself can subsequently increase insulin in the bloodstream. In other words, taking something that in increases blood sugar, attaching a flavor experience to that, having children or adults in just that thing, allows the nervous system to associate that flavor with that increase in blood glue cos. But then you can remove the glucose increasing substance, and the flavor alone will increase insuing, because insuing typically follows blood lue cose.

So this is a conditioning effect. Now the reason these data controversial is several world. First of all, the landscape around the discussion around artificial sweet nes is definitely what I would call a barbed wire topic. And I want to prefer what i'm about to say next by saying I actually in just artificial winners, I will have the occasional diet soda, not every day, maybe I don't know, once or twice a month.

I don't particularly like the taste, but i'll do IT just because it's around and I want some caffeine and I like the carbonation want to plan or something I do in just plant based non color ic sweater's. To my knowledge, there have not been high quality studies of plant based non color ic sweeteners in the context that i'm referring to here. Okay, none.

There's this study shows that particular flavors can be conditioned to cause in instant increase, and the flavor associated with certain artificial sweeteners is included in that category of flight verse that can induce insulin even in the absence of something that can increase blood. Luke OS, the simple take away from these studies, would be the following. And this is actually the one interpretation that dana small has offered to her data.

But SHE offered other interpretations as well. One of interpretation is that if people are going to ingest artificial sweet nes, and they do that along with foods that very sharply increased blood glucose, then there is the potential, I like the potential for those same artificial sweeteners to increase insulin even in the absence of food. In other words, let's just draw the scene oo out in the real world you're having a diet soda along with a cheeseburger and fries.

You do that every day for lunch OK someone extreme example, but natural world example. You do that every day for lunch and then you just have a diet soda alone. The extreme interpretation of the data we've collected says, well, that diet soda will increase in even though there is no increase in blood glue cos because you haven't adjusted, would do that because you conditioned that taste of artificial sweetener to the experience of a rising glue cos and has insuing.

Now the counter argument to this would be, well, that's a very unusual situation. Multiple xing causes big increases in blood glucose. So that's not really a fair experiment or it's not a natural world experiment. And I think that's A A decent assessment, although I will point out that one of the reasons why this study is so controversial or why these data is so controversial, is that the experiment actually had to be stopped.

In particular, the experiment in children had to be stopped because the changes in insuing that were observed early in the study were so detrimental that the institutional review board quite appropriately said, we can't do this to these kids. They are experiencing these odd shifts in insulin that are not healthy for them when they are just interesting artificial sweeteners in the absence of these glucose increasing. So once again, I do gest artificial sweet tens are not saying that they are dangerous and not saying, uh, that they are not dangerous, something that you have to decide for yourself.

In previous episodes, i've highlighted that artificial sweeteners have been shown in studies of animals that when given in very hypos, is super us. In particular, there can be fairly robust disruption to the gut microbiome, which is vital for immune health and brain health at, at, at, at. But thus far, our knowledge of how artificial sweeteners negatively impacts or positive ly impacts, I should say, the microbial and other diller's effects on the body has mainly been explored in animal studies.

Again, the work by dana small has been done in humans. There's some parallel work by others in animal models. I bring IT up today to illustrate the following point. Normally, we have a pathway that we don't have to condition at all.

It's there from birth whereby injection of sweet foods causes increases in dopamine and their parallel pathways by which neurons in our gut and elsewhere in our body trigger further increases in dopamine. So there's no need for a conditioned response or to become pavlovian about this, right? You're hard wired to want to eat sweet things by at least two and probably three parallel pathways.

Now the work from data is small lab and others that have illustrate this condition. Flavor preference, I think, beautifully show that any flavor that's associated with a glucose Spike or a long, sustained, increasing glue cose can also be conditioned. In other words, the circuits for dopamine that reinforce the desire to eat particular things is not unique to the sugar pathway.

And this is one of the reasons, I believe, why in gestion of sweet foods doesn't just lead us to want to eat more sweet foods. I think that is absolutely clear based on animal data and on human data, I think robots is actually the stuff of textbooks now. But in addition, ingesting sweet foods and our foods that raised blood glucose, but that we don't perceive a sweet sovereign foods with hidden sugars, sugars that have been masked by salty or spicy case, increases our desire for glucose, elevating food and food generally.

I think that's the only logical interpretation of the data that I can arrive at. So for people that struck with regulating their appetite or with really in the sugar appetite, I think the understanding of condition flavour preference, while a little bit complicated, ought to be useful in trying to navigate reducing sugar cravings and sugar intake as a segway into tools to control sugar intake as a means to both regulate sugar intake itself as well as food intake overall and steers towards healthier er choices. I'd like to talk about some of the special populations out there that might want to be especially wary of having a deregulated sugar appetite system.

And the group i'm referring to specifically are those with attention deficit, hybrid activity disorder or or I should say, and or people who have issues with focus and attention generally. And I think more and more novaes, i'm hearing that people are having a hard time focusing this probably have something to do with our interactions with electronic devices. As always say, if a pictures worth a thousand words and movie is worth a million pictures.

And the fact that we can access so many movies in just by scrolling with our thun is something that the nervous system has just never contended with before in human history. Confident that, and it's not that I can't deal with IT. The question is what's the trade off? What are the consequences of that? So attention, ability to focus is obviously key to success in school, success in relationship, success the workplace and success in life.

We could probably even go so far as to say one's ability to succeed in anything is proportional. The one's ability to focus, and then deliberately defocus when the time comes to defocus, right? Because we all need rest and we need to disengage, and then we engage.

If you look at the some total of the Better analysis and the clinical data on add and nutrition, you arrive at a pretty clear answer, which is that sugar consumption, in particular, highly refined sugars, is just not good for people with A H year of the tension issues. Now, as I say that, I also want you to recall the earlier study that I referred to, whereby the tuning of neurons in the brain is highly dependent on glue cose. So this doesn't mean consuming no glue cos is going to be a good idea, doesn't mean that the organic died is necessarily the best diet for adhd, although there are some people pursuing that and expLoring that.

And I will do yet another episode on hd at some point that goes a little bit deeper into the because there are some new data. I did A. Very long and fairly extensive episode and add you welcome to look that up if you like our our car excuse me, in our archive at huberman lab 点 com。

Um it's all time stamp. So uh you know because the number of people said, oh, you know it's an episode on a mate two and hf hours long. Yes, we did because we wanted to be as comprehensive as we could at the time. But IT is time stamps. You can just jump to the particular topics of interest and they're short little cassez there.

Now if you'd like to know upon what i'm basing the statement that sugar consumption and highly refined sugar consumption is potentially bad for adhd, basing this mainly on the conclusions of of a really nice paper that the title of the paper is sugar consumption, sugar sweden beverages and attention deficit hyperactivity disorder, a systematic review and meta alysa. And this is a paper and we ll put a link to this in in the caption this was publishing complimentary therapies in medicine, which is a bit of an a typical journal some sense but I really like this met analysis. Um the the some total of of this met analysis is really that when especially kids get beyond four sugar y drinks per week, so four sotos of typical to and soda, when they get past four two amounts sugar y sodas, they didn't, as far as I know, look at artificial, you sweeten sodas.

That's when you start to see a shift towards a more negative outcomes, more symptoms of existing hd. Now where the controversy comes in is whether or not sugar consumption can actually trigger or cause adage, and I don't think we can conclude that at all at this time. And this review, if you decided check IT out review, slashed analysis, I should say if you decided check IT out goes into some of the new ones around that.

What's also interesting in terms of A D H D intrigant take, and probably as relevance to all of us, is that they also cover some of the interesting data showing that supplementation with omega fatty acids can actually be beneficial for people in retailer kids with A D H D. I've talked before about the utility of omega trees that's been shown in various studies that have compared omega three fat accident take to a prescription into the presence like access is like projects are often similar fu ox. And the results of those studies are pretty clear, at least to me, that provided that one gets at least one gram of E P, A essential fatty acid, so it's not just getting one gramm per day, but one or more grammes per day of the E P A.

Former central radios can rival some prescription in her depressions and or decrease the amount of enter the presence that required to take, which for a lot of people, can be a very useful thing because of the side effect profile of many of those. Enter the presence, of course, talk to your psychiatrist, talk to your doctor. But the omega are no doubt powerful.

And then, of course, there is a whole story about I might get three and heart health. And of course, like anything else, there's some controversy around the mega series, but I think the data are clear enough to me around mood cardio. Ask your health that certainly I personally and just them, but as always, always say, anytime you're going to add or remove anything from your nutrition supplementation, exercise or other, why your lifestyle, definitely consult with a board certified physician.

I don't just say that to protect me. I say that to protect you, you are responsible for your health ultimately. So omega three supplementation has been shown to be beneficial for rad hd.

Why am I talking about this in the context of an episode on sugar in the nerve system? Well, if you remember those neurotic d cells, or cells in your gut that respond to sugar and send signals up to the brain to cause the release of dopamine, well, turns out that neuropace cells also respond to a mino assets and to fati assets, in particular essential fat assets. So these cells that we call neuropace cells have three jobs.

One is to detect levels of sugar in the gut. The other is to detect levels of a mino assets and to detect levels of particular essential fatty acids and communicate that information to the brain. And I should point out then, I say communicate that information.

They're not actually saying, hey, there's a mino ero. Hey, there's sugar hero. Hey, there's essential fats because the language of these cells is somewhat generic, is just the firing of electrical potentials. But that's the key point, is generic. And all three, or any of those three sugar, essential fat, acid or a minos, will trigger these neurons to single to the brain, increased opi mean and IT is not coincidental that a mega three fat acid supplementation can help emulate some of the symptoms of hd by way of presumably increasing dopamine in this neuro pod to dopamine pathway that we talked about earlier.

The whole thing has a very nice logical structure to IT and points to yet again the immense ve value of bringing the proper amount, maybe even supplementing the proper amount of a megory fat acid and the proper amount of a mino acids into the gut as a way to supplant some of the stimulation of these pathways that would otherwise be caused by sugar. There's actually a version of this where one could say, if you want to reduce sugar cravings, you might consider increasing certain forms of the mino acid intake, or certain forms of fatty acid intake. So what are some ways that we can reduce our sugar cravings, and ideally ways that we can do that, that also benefit us in other ways, with nutritionally, in from the neurosis standpoint.

Well, these neurotic sells that respond to and signal the brain when we adjust sugar, as I mentioned, also respond to a menu access. Essential fatty assets. We already talked about the essential fatty assets.

I make IT a particular point to injust, anywhere from one to three grams. That's grams of E. P, A essential fatty acid per day. I making a point to do that with the injection of high quality of omega three.

For me, the simplest way to do that, and I think for most people, the lowest cost way to do that, is to use some liquid form official or some castle former social. You really do have to see how much essential fatty s in the form of E P. A.

Isn't those if you trying to do that only through captions that can get kind of expensive depending on um which particular brand to use somehow more apa, some less. You can of course also do this through food. You can do this with non fish sources through things like L, G.

And there are some other forms you can look at up online. now. You plant the sources of epa. You do this with with high quality fishel.

In any case, that does seem at least based on a modest amount, but none's solid literature to reduce sugar craving somewhat, but that could easily be by mere replacement of calories, right? So we don't know yet, based on human studies, whether not the injection of those epa is specifically activating the neurology cells, which specifically activates dobin room release and bypasses the need for or the craving for sugar. We don't know that yet.

But but logically, IT holds up to assume that the fact that these neuroprotective ls, and I should say, other neurons within the gut respond very robust to the presence of particular mino assets, is also a potential liver by which one to reduce sugar cravings. And there's an interesting literature around the amino acid glue amine, in particular, supplementing with the amino acid glue to mine as IT relates to sugar cravings and certainly as IT relates to other aspects of the gut. In particular, leaky got the use of supplemental glutamine to try, and treaty ky got is not a new phenomenon.

There are other approaches to, of course, but there are many people who are experimenting with, supplementing with glutamine several grams per day, often even five grams distributed through three or four different services ings throughout the day, as a way to blunt their sugar craving. Now there has not yet been a large scale clinical trial using gloomy to reduce sugar cravings, but the results of the few studies that I looked at, as well as my understanding of the logic of these neural circuits, including the neuro pod cells, brings us to a conclusion that IT makes sense. Why, if there is a population of neuron to in our got, that responds very robustly to the presence of sugar, fatty acids or amino acids, that the intake of particular emini assets would allow the dopamine e pathways that might otherwise be trigger by sugar to be triggered by something like glue to mine, which has very few or no calories.

And in fact, having talk about this previously, uh, a number of people that I know went out and try this now this is, of course is what I call aneka data, right? This is not not a equality p reviewed study. This is annulled.

A um many of them have reported back that they actually feel as if their sugar cravings is are reduced. I know some people who actually take good to me to mix IT with full fat cream and take a company shot of full at cream sounds absolutely delicious, by the way. Good to me is a little but rocky.

So it's not that great tastings, ted. And just with sugar, I should mention if you do try and take this approach of interesting gloomy to reduce sugar cravings, you want to increase them out of glue to me that you take somewhat gradually. You can create some gastro distress if you just certainly won't take a big table spoon IT thrown water and chucked IT down three times a day.

Some of you with very Hardy stomachs can partly tolerate that. Feel like my, you know, my bulldog, which unfortunate passed away. But costello, I always imagine that if ever we in autopsy of me, he have like a license plate and like a human being and his gut, because he seemed like he could ingest anything with no issues.

But of course, many people have kind of sensitive guts. So if you're going to try taking glue to me as a means to reduce sugar cravings, just know that the studies are still ongoing. Some people have achieved benefit.

Please also realize that there's an entire literature devoted to the potential hazards of increasing glutamine if you have a in cancer. So if you have cancer or your cancer prone, I I would really discord you from this approach. In any case, as always, talk to your doctor.

The logic none's is there why increasing a mino accidental or fati accident take might decrease sugar craving? Now there are other ways to reduce sugar craving, and there are certainly ways to reduce the sharp rise in blood glue cos that can occur when we injust sugary sweet foods, or even just in abundance of carbo hydrate foods. And there are a huge number of these things i'm going to sort of layer up through the the ones that you might find in your cover, the grocery store and then get into some of the more um extravert should say esoteric ones.

Many of which however, um can be quite poor, the first of which is simple lemon juice, right or lime juice. There was an old law and actually some papers pointing to the idea that the injustice of vinegar, either White vinegar why or wine vinegar, could somehow black blood glue cos after the injections of sugary foods or the injection of a lot of carbon foods, even just a big meal. I see tim ferris.

I should take the great teferi s because I do have great respect for the fact that he seems to be about ten years ahead of everything um both in terms of nutrition and skill learning and things that sort of the things that he predicted in his books um the for our body and for our chef actually um turned out to be true based on scientific data some of which only exists in the animal models but now are also some predictions that uh that played out to be true in both the animal miles and in the human model so I think that tim certainly deserves um I had tip um for the fact that he experimented with these methods and and reported his experiences with those methods and that now some of them, many of them have been validated by what I perceived to be equality science he talked about the fact that at least in his experiments on himself, the injections of vinegar did not seem to the blood lucas, and he was using continuous glucose moors. These incidents, and another example of where fairs was early to the to the game in the rest of us, are kind of just in his wake. He talked about the use of blood glucose motors.

Those, I think at the time we're implanted below the skin nowadays, there are less invasive blue lucas monitors, things like levels and so forth, and these are actually becoming pretty popular. I've worn one of these before. They're actually pretty informative.

Um I learned, for instance, that when I go in the sauna that I experience a sharp rise in blood, lucas, and that make sense because of the dehydration associated with being in the song. A lot of sweating at concentration or sugar in the bloodstream goes up. Um so there's some other things that certain foods affect my blood glucose one way, and others interesting in fun experiment that some of you might be interested in doing as well.

Regardless, there are no data pointing to the fact that lemon juice and line juice a couple tablespoons ons or so if ingest ted before or even during or even after consumption of surgery foods, or I should say, foods that sharply increased blood. Blue coast or large couple of hydro als can actually blunt the black lue coast response. I did see that when I did my own experiments on myself with continuous cost, mother was kind of fun to do those experiments.

Um I preferred to do those experiments by eating somewhat larger meals of things that didn't contain a lot of sugar, saw some big increases in blood glucose in certain instances. And that I would adjust some some lemon juice or lime juice, typically mixed in with water. And sure enough, you could see a blunting of the blood lue cose response.

Of course, this was real time blood continuous, hence continuous blood lucas monitoring. So for those of you that are interested in blunting your blood sugar response, certain foods, that's a simple, low cost way to do that. If you want to export, I will say if you are fasting and you already have low blood glue cose, and you injust lemon use, or I just some lemon juice water, ledin water, be careful, because you can actually become hypoglycemic, right?

For the very same reasons that these uh the lemon juice and line juice can blood blood glucose. When your blood glucose levels are moderate to high, you can also reduce blood glucose levels even further when like gos levels are low. Now that's lemon juice and lime juice there, but we can say that has to do with acido things generally.

And just as a sideband of you would probably seen in the store so called adjusted p waters or foods and drinks, there are supose to adjust your hate to break IT to you, but your pis very tightly regulated throughout your brain and body. You do not want this to change. IT is entirely impossible, at least in any safe way, that you would become cost more alcove by interesting, and along water, something like that.

IT is true that the PH, your alcohol di and acdd varies in different compartments in your body that's important unless you are emerging or vomiting or there's something badly wrong with you healthwise and you're a really dire circumstance. You don't want big shifts in your body. P in your body has all sorts of ways of buffering against changes in PH. So um encourage you not to fall on the or hop on the bandwagon of adJusting PH from becoming less acidic and that kind of thing when you just lemon juice or line juice.

The mechanism by which a blunts blood glue cose is probably too fold one is probably through the post injection ve effects of glucose in the gut, meaning the way in which sugars are interacting with neurons and other components of your gut circuitry to impact things like gastric empty time, to impact things like the firing of those neurologic ells in their signaling to the brain. But almost certainly, IT has something to do also with the perception of sour taste on the tongue. We didn't go into this too much today, but you, of course, don't just have sweet taste recept tors in your mouth.

You also a bitter taste. You have salty taste receptors, you have sower taste receptors in your mouth. And on your end, of course, that means your tongue and poet, and those are interacting if you, in just a substance that's just sweet or mostly sweet, that causes a certain set of effects on your blood blue coast, but also your brain, dopamine and the other neural circuits of your brain.

If you also in just something that sour, like lemon juice or lime juice, IT adjust the output of those neural circuits in your brain. So again, we have a situation. We have two parallel pathways.

One that's post justice ves coming from phenomenon within our gut neons but also thinks like gesture camping time, the clearance and the transfer of food and the conversion of food into particular nutrient and the circulation of blue coast in your bloodstream and how he gets into the brain, but also simply by ingesting something sour, you are changing the way that sweet things impact your brain. And so I think IT stands the reason that the lemon juice, lime juice effect is not going to be magic. It's going to have everything to do with the way that ingesting sour foods can adjust the taste, excuse me, can adjust the neural response to taste of sweet foods.

And in fact, we know, based on the beautiful work of Charles suker at columbia medical school, that that's exactly what happens. They've measured the the activity of neurons at various locations in the so called taste pathways of the brain. And they found that when particular taste like just sweet or just bitter or just sour, evoke certain on subs of neurons to fire in particular sequences.

When sweeten sour, co injured ted, when bittern sour or coco injustice, you get distinct on sambas, meaning distinct patterns of activity of those neurons, and of course, distinct patterns of downstream activity within the brain and body. So while IT is still somewhat mysterious as to how exactly things like lemon juice and lime juice can reduce our blood blue cose Spikes when we inject s with sweet foods or carbo hylax foods or with big meals, you can use this as a tool with the understanding that there's a grounding in the biology of the way these circuits work. Now some of you have probably heard that can be a useful tool for controlling blood sugar.

Indeed, that's the case. It's very clear that cinema can adjust the rate of glucose century into the bloodstream, possibly by changing the rate of gastric empty. IT might slow the rate of gastric empty and thereby also reduced the glycemic index of particular foods.

So I suppose if I were going to eat a mango, and I hadn't just done a bunch of heart training, I might sprinkle some cinema on IT here. I always enjoy going to coming up with new ideas of ways that I can eat foods during these podcasts. In any event, there's some debate out there if you look online as to whether not cygnus inmate casa cinnamon, excuse me, or say on is best for purposes of of blunting blood lue co bikes.

But I think the at least by my read of of the data and from what I found, IT doesn't really matter, provided its real cinnamon, and you have to actually look and and make sure that it's real cinnamon, because a lot of cinnamon that you buy is not real. I do want to provide a cautionary note about cinema. However, cinnamon contained something called cumin, which can be toxic at high levels.

So you don't want to just more than about a teaspoon, maybe a teaspoon and half of cinema per day because you'll start to exceed the threshold at which cinema could start to be problematic. But certainly, if you're going to have a big meal or a meal that has A A lot of sugar in IT or a lot of carbo hydrate um laden foods, and you don't want an increase in blood glucose, you could put cinema in a beverage, you could put cinnamon on food in order to blunt that bad glucose increase. Reduce the licensing c index by way of reducing gasters camping time.

Again, just making sure that you don't get out past that one to have tea spoon ons per day because you really don't want to start dealing with any of the toxicity related accommodate. So we've talked about lemon juice and lime juice and cinnamon. These are kind of common place in many kitchens.

Then of course, we can venture into the more a service, or I would say, the more advanced tools for adJusting sugar intake. And the one that comes to mind is, of course, burberry. Burberry is a derivative of tree bark and is a very, very potent substance for reducing blood luco.

So much so, that is on par with metformin, or glib on command, which are prescription drugs specifically used to reduce blood glue cos. So using burberry is a serious step. You should absolutely, we talk your doctor about IT.

I know of a number of people that use IT to lower blood lue coast when they eat really large meals. I know a number of people they are using IT to get to some of the other effects of met forming that people have discussed, things like activating or tapping into the so called A M P K pathway, reducing M R. These are people are aiming their activities that, uh, increasing longevity of somewhat controversial approach still.

But I know many people are doing IT. IT is true that if you injust burberry, your blood lue cose will plump. And I point that out because i've actually tried IT before.

I gave me brutal headaches. And I felt really dizzy, and I felt like I couldn't see straight. And actually, I couldn't see straight.

Why did you do that? Well, I may meet hypolito. I could actually drove my blood lue coast down too far.

And the reason is that is that I took burberry on an empty stomach. I know some people can tolerate IT. I would say be very cautious about ingesting burberry on an empty y stomach.

Or if you are in a low carbon herte diet, unless you really know what you're doing and you have a medical professional to kind of guide you through that, if I took burberry, along with a very large meal that include a lot of couple of hydrates, I can recall the days in which cost still. And I would eat a couple of pizzas and then we might get ice, scream that kind of thing. Then I felt perfectly fine.

On even up to seven hundred fifty milligrams or a gram of burberry, IT has the kind of unique property of making you feel not overwhelmed by the amount of blood lucus increase that you're experiencing from meeting a big meal. I don't quite know how else to describe IT almost as if you can keep eating and eating and eating and of course you have to um protect your gastric volume, right? I mean you only have so much space in your stomach and just food.

Um I wasn't using IT to gorge on food. I just heard about IT. I was interested in experimenting with that. I don't have any chona blood sugar issues but again, when I took IT on an empty stomach IT made me hypoglycemia on a low carbon hydronic hypoglycemia not a good experience um and again an experience I think to avoid.

But provided there's a lot of glucose in your bloodstream and certainly if you are of the experimental type where you're trying to regulate black luck s burberry might be a good option. But again, talk to your doctor. He does have some other interesting effect terms of lowering total cholesterol that are research supported of um reducing insuing a little bit but that's not surprising if you reduce blood lue cowered going to reduce insulin because of course insulin manages blood glue cos in the bloodstream.

But so I would place burberry, and of course, met form in england bank mid, in the kind of the heavy hitting, potent tools for the regulating blood. Lucas, now this is an episode not about sugar persae, but sugar viewed through the lens of the nervous system. And what's interesting about burberry, mat forming glib km de and related substances is that some of the effects are, of course, on gastro campaign or buffering blood lue coast within the bloodstream at set up.

But there appear to also be some neural effects of having chronically low glue cos or blunting blood glue cos through things like burberry. And some of those neural facts include long standing changes in the hormonal cascades that are the consequence of having low blood sugar, and thereby changes in the neural circuits that manage blood lucus overall, the simple way of saying this is that by maintaining low to moderate blood glucose, either by not interesting heavily carbon hydrate laid in foods. So here i'm speaking to the low carbon, to the key jenni c types, or by black unting, black lue cose through things like meat form and or burberry, even if ingesting in carbo, hydrates, tes, maybe even some showers over time, IT seems that there is a adjustment, what we call a homeostatic regulation, of the neutral circuits that control things like sugar craving.

And indeed, some people report feeling fewer sugar savings over time. Now I didn't use burberry for a very long period time. I've never used my forming.

I have experienced to somewhat odd but welcome phenomenon of with each progressive year of my life, I have fewer and fewer sugar cravings. Why that is, I don't know. I suspect you might have something to do with my sleep, and i'll talk about that in a few minutes.

But if you're going to explore burberry or metformin or otherwise in addition to working with a doctor, I think you should understand why you're doing IT, right? I think that many of the effects can be quite poor. They can happen in both the immediate term in terms of regulating blood lue cos, they can send you hybrid, I see me if you aren't careful.

They can also cause long standing changes to the neural circuitry that regulates blood sugar over time, some of which might be welcome changes, right? Reduce sugar cravings, for instance. And if you're really, really serious about module and blue blue cose through things like burberry, the typical dose range again is anywhere from half a gram to one point five grams daily that the typical dosages that have been explored.

And there are some other substances like sodium corporate um which are known to augment the effects of burberry via the M P K pathways. They basically can increase the ability for burberry to have its google slowing actions. But that of course is getting into the really poor, what I would call sharp blade tools for controlling black lucus.

And listen, anytime you are dealing with black lucas, you are dealing with the brain's preferred source of fuel. And any time you deal with the brain's preferred source of fuel, you have to be especially cautious about depriving the brain of what IT needs. So whether or not your low carb, high carb um you know kedo, vegan, carnivore, these substances like burbery are very, very potent and you need to take them seriously.

There is yet another tool for controlling sugar cravings and the neural circuits that regulate sugar craving and its downstream consequences. And this tool is what I would call a high performance tool, but it's one that you probably didn't suspect. And that's sleep.

I've done extensive episodes about sleep, and we actually have an episode called master your sleep. You can find that epo de easily at huberman lab doc com is available in all the various format, youtube or spotify a and provides a lot of tools. And on social media, I provide a lot of tools.

Often we have a news letter that provides tools and how to maximize sleep. What is the role of sleep in sugar metabolize, sugar hunger and the way that the brain regulate? Tes, those things.

Well, there's a really exciting study that came out just last year. This study was publishing the journal cell report, sell press general, excEllent internal. And the reason I love this study so much is that involved having people.

So yes, this was done in humans sleep in the laboratory. That's not unusual. There's a sleeping lab at stanford is sleep blab elsewhere.

But what they did was they actually measured from the breath of these people, and they extracted from their breath the metabolic ts that would allow them to understand what sorts of metabolism was occurring in these people's bodies at different phases of sleep. And this is a really remarkable study. They actually did this every ten seconds throughout the entire night.

So in little, tiny, ten sacred bins, in very high resolution, they could evaluate what is the metabolic in the brain and body that people experiences. They go from ramos' ep, rapid eye movement, sleep to slow wave lep and so on. And i'll go deeper into the study again in the future because it's so interesting and I think so important.

But what they discovered was that each stage of sleep was associated with a very particular signature pattern of metabolism, and particular phases of sleep are associated with sugar metabolism, or more with fat metabolite, or more with other aspects of metabolic. And the reason why think this study is important to discuss in the context of today's discussion about sugar in the brain is that many people have experienced the effects of disrupted sleep on their appetite. And in particular, it's been reported that when people are sleep deprived or the quality of their sleep is disrupted, that they're appetite for sugar y foods increases.

Now that was always assumed to be due to some metal bolic need that was triggered by the sleep deprivation by the poor sleep. But in reading over the studies, some of the more important points made by the authors relate to the fact that, well sleep is known to have incredibly important effects on brain, body, a variety system, immune system, neural functioning, eta, this very organized sequence of particular forms of metabolic being active during particular phases of sleep, which are very, very well orchestrators. We know slow wave sleep in RAM sleep being orchestrated ninety minutes, so called all treatment cycles and so on.

And so for is thought to perhaps set up the brain in body to be able to regulate itself in the waking hours. And therefore, when people are sleep deprived or deprived of certain forms or states within sleep, such as rapid I movement sleep, that IT creates a disruption in a particular set of metaphor c pathways. Now we don't want to leave too far from this study to sugar metabolite in the neural circuits controlling sugar metabolite m.

But I will say this, if you look at the same total of the data on obesity or on type two diabetes or on metabolic syndrome, any kind, you almost always see disruptions in sleep. Now some of those could be due to sleep up near caused by even just the size of somebody's neck, or they wait of their body in other ways. We don't know the direction of the effect, right.

Media lic synergy could disrupt left, which disrupt metaphoric systems. And indeed, the authors point out quite appropriately, that they don't understand the direction of the effects that they observe either. But there is now a pleasure of data pointing to the fact that getting quality sleep each night helps regulate not only appetite, but also the specific forms of metabolism that drive specific appetites.

So the takeaway is, while there are extravagant and potent and interesting ways to regulate glucose, from cinema to lemon use to burberry to sodium corporate to behavioral tools to the mira, understanding of how the direct and indirect pathways go from the gut to delph unit, ta, if you're not establishing the firm foundation of proper meta lisp, all of those things are going to be sort of arranging debt chairs on the titanic as as IT sometimes described. So we can't overstate the importance of getting regular, sufficient amount of high quality sleep, at least eighty percent the time, not just for sake of immunity stem function for clear thinking is set up, but also for properly regulating our metabolism, including our sugar metabolism. Thank you for joining me for this discussion about sugar and the nervous system and how they are regulating each other in both the brain and body.

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