DO THIS To Improve Your Mood & Master Your Mind | Wendy Suzuki

I think it is absolutely clear that exercise can help with attention span, with memory, with mood and engagement. Exercise does really profound things to the brain. And I think one of the secrets of exercise is that it's affecting so many different systems. It affects heart rate and blood flow. It affects oxygen levels. And one of the things that we know that is really key is that it affects the levels of growth factors that are in particular very important parts of the brain to key areas are an area critical for long-term memory called the hippocampus. We know that there's increased growth factors there. And a second key brain area important for focusing and shifting your attention, that is the prefrontal cortex. So there are many different effects. And I have to say that I don't think we understand the full range of all the different physiological changes that happen in our brain with exercise, but that's just a few of them that happens that cause things like changes in transmitter levels that improve your mood, and changes in these growth factors that actually improve the function of both long-term memory as well as attention. There are forms of exercise that we know a lot about. The most work has been done on the effects of aerobic exercise. That is, exercise that increases your heart rate. And so we know that is particularly useful and effective at improving your brain function. There's less known, but some known, about resistance training, so weight training. And there's mixed results there. Some reports say, yes, it is beneficial. Other reports don't find a beneficial effect. It's hard to say whether we just don't have enough studies looking at it, but if you really want to stick to the kind of exercise that we know the most about, it is aerobic exercise, cardio exercise that gets your heart rate up. Intensati does two different things. It gives you a great cardio workout with the kickboxing and dance and yoga moves, but it also layers on those key positive affirmations. And that does at least two different things to your brain. The aerobic exercise is improving your mood by increasing neurotransmitter levels of transmitters like serotonin and dopamine and noradrenaline. And that increases your mood, but also has effects on memory and attention. The affirmations, we know that positive affirmations alone can also improve your mood. So you can think of intense AT as a workout that not only gives you the benefits of aerobic exercise, but gives you a double boost of mood boosting neurotransmitters in your brain. One of the most exciting findings in recent neuroscience research is findings showing that if you give rats access to a running wheel, and you can show that they are running significantly more than their brothers and sisters that don't have the running wheel, What happens is you stimulate the birth of brand new brain cells. These are adult rats. So there's in adults, brand new brain cells being born in the hippocampus, a key area important for long-term memory. In those rats that have access to the running wheel, they not only have more hippocampal brain cells, but they actually learn and remember better than those brothers and sisters that are in the cage with no running wheel. So they are essentially strengthening the function of the hippocampus, which is to allow you to form and retain new long-term memories for facts and events. There's some evidence in humans that this is the case as well. It's actually been demonstrated much more clearly and much more extensively in rodents, but my studies looking at the effects of aerobic exercise in healthy young adults are starting to show the first evidence that recognition memory, that is memory that allows you to say, yes, I've seen you before, or I haven't seen you before, is actually significantly improved after three months of increased aerobic exercise. This was after I realized that exercise seemed to be not only improving my mood, but my memory and attention were better. I wanted to learn more about this topic. And as a professor of neuroscience, I know the best way to learn about a new topic in the field of neuroscience is to teach a new class on it. So I decided to teach a class called Can Exercise change your brain. Can exercise change your brain? And this class was going to go over all of the animal studies looking at the effects of exercise as well as clinical studies in people looking at the effects of exercise on brain function. But I thought, wouldn't it be fun to actually bring exercise into the classroom? And so when I went to the administration to ask, could I have some extra money to hire an exercise instructor so we could have, we could all exercise together and then I would tell them about the effects of exercise on the brain. They said, well, we pay you to teach these classes. There's no extra money for an exercise instructor. So I decided to do the next most obvious thing. I decided to go to the gym myself and get certified as an exercise instructor. And because I was going to all these intensati classes, of course I decided that I wanted to become an intensati instructor. So that started the first of six months of intensive training to teach a new class. It was the most extensive preparation I've ever done for a class that I've ever taught at NYU. It really shifted things for me because if I can bring you back to that first day of that first class of can exercise change the brain, there were three things that were really different that day. The first thing was I came to class in my best Lululemon because I had to teach exercise class. I usually don't I usually don't teach in Lululemon, but that day I was teaching exercise. The second thing was I was really nervous, and I don't get nervous lecturing in front of students. By that point, I'd done it 15 years, no problem at all, but I'd never taught an exercise class. The third thing that was different was the students themselves. So this was the first day of the fall semester. Everybody's a little bit excited, you know, don't know what's going to happen in a new class. These students look scared. I don't know if it was me and my Lululemon, but they, I could tell in their eyes they were not sure they really wanted to be there. So they were ready and I knew that the only way to tell whether this was gonna work was to actually start class. And I can tell you that it really shifted the mood in that classroom from one where there is a all-knowing professor just talking, talking head at the front, to much more of an interaction. So when you work out and shout silly and positive affirmations with your class for a whole hour before class, it changes the dynamic. And I got so much more interaction, so much more engagement and involvement. It really did change the way that I taught every class since at NYU, but more importantly, did it change their brains? I actually set the class up so that I can test them cognitively at the beginning and the end of the semester to see if this increased exercise changed their brain. And I also tested a control class that didn't exercise during the semester. the semester. It wasn't very hard to find one of those. So I compared the two. What I found was significant improvement in reaction times. So they answered the memory questions faster if you were in my class compared to the control class. And that was really exciting to me. It was a small but significant effect, but that was only once a week. And I came away from that class thinking if I could get a significant effect after just once a week increased exercise in these college students, what would happen if I got got them to exercise for three times a week. So in fact, I've just completed a pilot study with freshmen in which they did a one semester increased exercise compared to a one semester no change in exercise. What we found were significant improvements in attention, significant improvements in mood, significant improvements in short-term memory, as well as significant improvements in that thing I was searching for, long-term memory improvements. So we're starting to see these effects and we're going on to do many more of the thousands of students that I have at NYU to test. But this is one of the big research directions in my lab. One of the major goals of my research program, what is the optimum exercise prescription for a student? I'm starting with college students because that's who I have access to, to improve their ability to learn and retain and be creative during the learning process. I think it is a huge mistake to take away physical education from everybody from, you know, elementary school to high school students. I think it is absolutely clear that exercise can help with attention span, with memory, with mood and engagement. And one of my goals is to find what is that optimum prescription. When do I have to give you exercise to maximally benefit your school day and your learning possibilities? So yes, it's critically important and I'm just trying to develop the kind of the data to be able to demonstrate what are those answers? A key question is how exercise might be able to reverse cognitive decline that you might see in aging. So the vast majority of studies looking at the effects of aerobic exercise on brain function and cognition have been done in older adults where we know that there is a decline in cognitive function. So how is it doing it? Well, It's doing it because it is enhancing the function of two key brain areas that we've already talked about that we know are particularly sensitive to aging. One of them is that key area important for long-term memory called the hippocampus. And the second one is that key area important for attention and also decision making that is the prefrontal cortex. So through these mechanisms that increase growth factors, that basically help both the hippocampus and the prefrontal cortex work better. You are helping these areas that in aging are already starting to decline, work better, so work at their maximum function. But I think it's even more interesting to think about what is exercise doing to young and middle-aged people. So young and middle-aged people, what they're getting is even more birth of brand new brain cells in your hippocampus. So you can think of the hippocampus as like a muscle. So the longer you work it, the bigger and fatter and more functional hippocampus you get. Similar for the prefrontal cortex, you don't get new cells there, but you enhance the connectivity and synaptic function of the prefrontal cortex. So what's happening as you're exercising regularly through your young life and middle age is you're basically strengthening these two key areas. And even if you have Alzheimer's disease or dementia in your genes, it's not going to change that. What it's going to do, it's going to make those diseases work longer and harder to show those effects on your behavior so that you're gonna basically last for a longer time with higher levels of cognition. Why? Because your prefrontal cortex and hippocampus are stronger and they work better because you've been exercising. There are two reasons why I started to study the effects of exercise on the brain. One of them I've already said that as I found this and I noticed this profound effect of aerobic exercise on my own brain function. I had much much more energy, I was in a great mood, I could focus my attention and my memories better. And that led to this course that I taught at NYU and that was one of the major reasons why I wanted to study this. This was a critical area of research. And I should also say that I wasn't studying this before, I was studying the hippocampus and how it works for memory. But this new area is much more practical. How can we use exercise and what is the exercise prescription to improve your brain function? But in parallel with with that observation on myself. My father actually developed a very, very sudden decrease in his memory function. We still don't know why, why this happened. But what I noticed in him, and it was so clear because it happened so suddenly, is from one day to the next almost, several weeks before versus several weeks after, he lost some of these key brain functions that were improving. in myself. His memory went downhill. He couldn't remember how to drive to the 7-Eleven, which is literally seven blocks from his house. He's been going there for 30 years, and he couldn't remember the way. And that's what really tipped us off to something was going on. And also, his attention span shifted. He's a very smart man. He remembers, and he could pay attention very, very well. And it was clear that he still had that knowledge. but those key functions that I study were clearly deteriorating. Now, my father's 86 now, and I can't just say, okay, go out, go jog around the park a few times, Dad. But this kind of became the impetus to think about how can I get more people to have better memory for longer periods of time? And for me, the answer was, start young, start with the college students, start with the high school students so we can work them through the system and get their brains as strong as possible. Not to say that the work on older adults is not useful and very, very important, but that was my motivation from my personal experience. So the title of my book is Healthy Brain, Happy Life. And it's not to say that you absolutely have to have the most healthy brain in order to have a happy life. but it really was the distilling of my personal experience. For me, it started with losing this 25 pounds that I had gained and really getting much more fit and noticing how much that changed my brain function. But as I said, the first thing I noticed was improved mood. I was just happier when I was going to the gym. And you'll, you ask whole rooms of people. Who notices that they feel better when they take a walk and everybody's hand goes up. But that isn't quite enough for everybody in the room to get on that regular exercise routine. So for me, the exercise led me to better mood and it led me to an area of research that has been just so fulfilling for me right now. How can I bring exercise into the classroom? How can I bring get more people across the country to improve their exercise regime because I know what it's doing for their brain. The thing about the brain is that it controls everything. How we see, feel, touch, experience, hear, the world. The brain responds to novelty. So a great way to bring new plasticity, new experiences into your life is to try new things, and that could be at lots of different levels. You like food? Go try lots of new flavors. Explore, you know, all the different ethnic cuisines or unusual ethnic cuisine. You don't have to eat it all the time, but just exploring that and noticing the differences between what you usually eat and this new cuisine is going to encourage new pathways to form in your brain. The old suggestion of, you know, try to do things with the opposite hand. So I'm right-handed, I brush my teeth with my right hand. So to encourage new plasticity and new pathways to form in your left hand, try and brush your teeth with your left hand. It may not be as efficient, but with a little practice you'll be surprised at how good you get at doing these things. So small things like that. One of my favorites is an exercise that was suggested to me by an artist friend, which is, and this is to enhance your visual system, I love going to a museum, but I like kind of strolling around and looking at art as I stroll past. Maybe I'll stand for a little while, but she suggested sit down for a good 15 minutes and really explore all different levels of this painting. Each individual subsection, the overall gestalt of the painting, and really spend some time in and think about what the artist was trying to do. You don't have to be an art critic, but what do you notice? What does your visual system tell you? It's a whole new way to look at art and to stimulate your visual system in a new way, and it's fun if you're going to a museum. That's one of my best brain hack tips. So creativity is a really hot topic, and I became interested in creativity because this key structure that I've studied for the last 20 years of my career, the hippocampus, has recently been linked to a form of creativity. So since the 1950s, hippocampus has been linked to memory, long-term memory function. Everybody, every student of neuroscience will know that the hippocampus is important for memory. But more recently we've realized that the hippocampus is not only important for thinking about and remembering things from your past, but it's also important for imagination and putting things in your knowledge base together in new ways, which is a core aspect of imagination related to creativity. How do we know that? We know that because people that have damage to their hippocampus, we all know they have amnesia, they have memory impairments, that's not a surprise. But recently it's appreciated that not only can they not remember things that they've experienced in the past, but if you ask them, could you, describe a situation that you've never experienced before. Let's say you've never been to a tropical beach. You might have been to the beach, but it wasn't tropical. If you have a hippocampal damage, you have a very hard time in pulling together that new kind of information. Even though you have the knowledge to be able to understand, and it's not a language deficit, it really does seem to be a specific deficit in pulling together information from your database in new and imaginative ways. So that suggests that that same exercise that's enhancing memory function because you're enhancing new neurons in the hippocampus may also enhance your ability to imagine new situations. That might be critical if you're a high school student or a college student. And that is one of the questions we're asking in my lab right now. My top memory hacks are based on how we know memory works. So how do you form a new memory? You remember things that are very new. You know, a pig walks into your classroom, you remember that because pigs don't usually walk into the classroom. So novelty. Repetition. So of course the old adage just repeat, repeat, repeat. The memory system is designed to strengthen upon repetition. Third, association. So if you can link a new piece of information that you're trying to learn with something that is very well known to you, that will help you remember that. Our memory systems are very good at forming new associations. And fourth, emotional resonance. We remember things that we remember the happiest and the saddest moments of our lives because it turns out that another brain structure, the amygdala, can particularly particularly help enhance those emotionally charged kinds of memories, either positive or negative. So those are my best brain hacks. Exercise is not only enhancing all these great growth factors and helping your hippocampus grow, but it does protect us against stress.

And.

It'S actually unclear exactly how it's doing that. And the surprising thing, the kind of incongruous thing, is stress stimulates the release of a stress hormone, cortisol. And too much cortisol can actually first damage and then kill hippocampal cells. It turns out that exercise is a stressor as well. It will also increase cortisol levels, but the cortisol released with exercise seems to protect the hippocampus from the kind of fire-related, you know, the really stressful-related cortisol release. that you have. We're still not clear on how it does it, but we know that exercise can protect the hippocampus in particular from the deleterious effects of stress induced by negative happenings in your life. So I think my take-home message for everybody is you can start small, but walking is the next step to increasing your aerobic exercise. You don't have to become A triathlete. It can start small, but start it, be regular, and gradually build up. And there are so many great apps out there to help you do that in a seamless way. But so important to get that regular exercise. My second big tip is do something that is fun for you. Don't do the most popular thing if you hate it. Find something that you love. If you love working out with your friends, find friends that will work out with you. If you love being outside, find something you do outside. Everybody can find something to do to make their life more physical and you can start small.

Just getting into colder water, taking a cold shower or exposing your wearing your skivvies like on your terrace during the cooler months can all be a great way of activating these ancient thermoregulatory mechanisms that we all have in us that we've allowed to gather dust because we all live in a state of of chronic climate control. And I think that by staying in that climate comfort zone all the time, it undermines some really powerful reparative and restorative pathways that we have in our body.

So what's the science of that?

Well, I mean, being exposed to cold air boosts the proliferation of brown fat. So, I mean, we're all afraid of gaining even more fat on our waistlines and on our hips, but brown fat is actually something that we want to have more of. It's metabolically active. It's brown because it actually has a lot more mitochondria than normal white adipose tissue.

Which are the energy factories in your cells?

Energy factories in your cells, yeah. They give you more energy, but they also, this brown fat actually burns fat and it burns sugar. And we can actually increase the amount of brown fat that we have on us. It's not actually visible. You can't see brown fat. It only accumulates in a few parts of the body. In our armpits, around our collarbone, down our spines, shoulder blades. That's where you're gonna see the brown fat. You can't actually see it because it's really relative to the amount of white fat that we carry. It's a very small in concentration, but it's really good for our metabolic health. So whether that means turning down the.

Thermostat-- you- get more brown fat if you expose yourself to cold.

Yeah, because brown fat, it burns calories to generate heat. So when you're in a cooler environment, this brown fat is burning calories to generate heat. Brown fat was actually originally identified in babies. Babies, when they get cold, they can't shiver. Babies can't shiver. So they have this brown fat that basically acts like an internal heating pad. And for that reason, it wasn't known whether or not we carried this type of fat with us through adulthood. But now not only do we in fact carry this brown fat with us, which acts like an internal heating pad that burns calories, as I mentioned, but we can encourage its proliferation.

Yeah, well the Tibetan monks knew this for years. They have a practice called tummo. Do you know about this?

No.

Tummo is amazing. It is a technique called drying of the sheets. And so they train the monks to activate their brown fat through meditation. And they have them up in the Himalayas and the monasteries way up in the freezing mountains. And they practice by dipping cold sheets in ice water and they wrap the monks in the sheets. And the monks have to dry the sheets with their internal body heat. and when they can do that, they send them up overnight into the snow with basically a loincloth and they have to stay alive.

Wow. And they do.

It is quite an amazing practice and we've had such a surge of things like saunas and cryotherapy. And, we haven't talked about it on the show, but there's something called zombie cells. Zombie cells? Exsenescence cells. Yeah, the things that tend to kill us where these sort of senescence or aging cells and they just create a lot of nasty immune effects and inflammation in the body, and it's hard to get rid of them. Cryotherapy or cold exposure is one of the key mechanisms for getting rid of these zombie cells to help extend longevity. And personally, you know, I found that when I was really sick, and even now it's a standard part of my practice, I go into a hot sauna or a steam, get really hot, and then I turn the big bathtub, only cold water, and I jump in. Wow.

And it's pretty invigorating, but you feel.

Afterwards like your whole nervous system is awake and you're alive and you're energetic and it clears your head. It's pretty striking. Yeah, it is striking. It's. And when I had chronic fatigue syndrome, it was one of the few things that gave me, like, a half an hour, an hour of feeling some respite.

Wow.

Yeah.

I use that, that therapy regularly for. I have low back issues. I think a lot of people do. I feel it's like a powerful analgesic, like, it's. I get instant pain relief. Yeah. What it does for my mental acuity and my mood is, I mean, there's, I don't think that there's a drug as powerful as what that does.

And it's, there's a jump in a cold lake.

It'll wake you up. It'll wake you up.

Yeah.

But I also want to mention before, before moving on from cold, that there have also been a number of studies where they've taken people with type 2 diabetes, which is very common.

Many people have blood sugar issues, you.

Know, pretty much every other human in America. Yeah. And they found that when taking subjects with type 2 diabetes and exposing them to just mildly cool I believe anywhere between, I think it was somewhere between 60 and 66 degrees Fahrenheit, which is not super cold. By making no other changes to their diets or lifestyles, they were able to achieve a 40% improvement in insulin sensitivity, which is an effect size that you would expect by putting these patients on a new exercise regimen. Just exposing them to cooler temperatures.

Wow, so you don't have to get out of your chair, you just have to freeze?

Just activate that brown fat. Yeah, leave your thermal comfort zone. at the end of your comfort zone, your best biology.

Well, that brings up the next subject, which is nature is medicine because we're so isolated from nature. Both the light experience we have isn't based on natural light cycles. The temperature experiences we have aren't based on being exposed to the environment like we always have been. And it has really detrimental health effects. So, you talk about nature and how that is really the disconnection from nature is really a source of problems for us.

Major. Today, we spend 93% of our time indoors, in big cities, and there's a lot of this research now coming out of Japan on forest bathing. There's actually a Japanese word, I believe it's keroshi or karyoshi or, I could be butchering it, but essentially there's a very significant portion of the population that gets worked to death in Japan. And there, I mean, 93% of Japanese people live in cities. So they are far removed from nature. And so this nature bathing line of research has really become a major focus.

Wow. Yeah.

And it's now being studied increasingly around the world, the relationship that we have with nature, especially as our cities become more and more dense and more and more polluted. But in the Genius Life, I talk all about how air pollution can affect cognitive function and put us at increased risk for Alzheimer's disease. 20% of Alzheimer's cases might be owed actually to heavily heavily polluted air. And today, 52% of Americans live in environments with heavily polluted air.

Isn't there like there's some like UV app on your phone where you can tell the air quality.

The air quality index. Yeah, you can, I believe you can actually, I think the weather app on an iPhone tells you the air quality. But yeah.

My niece lives in Houston. She says every day they get warnings not to go outside.

I mean, it's scary. And our indoor Your home air can be just as polluted, if not more polluted, than outdoor air. It can be. But in regard to outdoor air, what I think is really the most pressing of concerns where brain health is concerned is what's called fine particulate matter. So airborne particles that are two and a half micrometers or smaller that are actually able to enter, we breathe it, we breathe these particles in, they enter circulation and they can pierce the blood-brain barrier and enter the brains. And they're doing studies now in very polluted parts of the world, like in Mexico City, where they'll take children and they'll actually see these particles like magnetite, which is made of iron, in the brains of children. And what's very interesting, Mark, you know Rudy Tanzi up at Harvard doing all this research on viruses in the brain and how it can-- the microbiome of the brain. Yeah, the microbiome of the brain and how amyloid might be a response to.

An inflammatory insult in the brain. Amyloid is like the gunk that clogs up your brain if you have Alzheimer's and it's sort of a response to inflammation, sort of like a Band-Aid in a way.

Yeah. What they're seeing now is amyloid presence in brains of people who have inhabited very highly air polluted areas with very high level concentrations of air pollution. Yeah. So, whether it's like magnetite or other fine particles or the herpes virus, amyloid is like this protein which may be actually coming to the rescue. But the point is, that being in a place where there's a high concentration of air pollution might actually be creating this inflammatory insult to the brain, which is causing this very early presence of the pathologies that we associate with Alzheimer's disease.

So connect back to nature because you were saying we should all move out of cities and become farmers.

More connected to nature, yeah.

That would be good.

Yeah, I mean there are some things that you can do. So spending more time in nature, I think is super important, especially if you are at heightened genetic risk for Alzheimer's disease. So, if you're an APOE4 allele carrier, making an effort to spend more time in nature.

That's a gene that increases your risk. If you have two of those genes, like getting Alzheimer's by 45.

14.4, yeah. So, doing that, also getting out in nature is crucially important because of the exposure to the sun. So, exposure to the sun, I think, is very important. We were talking all about circadian biology, exposure to bright light, crucially important. Vitamin D deficiency is thought to be a risk factor for developing Alzheimer's disease. There's a review of environmental risk factors that I talk about in the book, and vitamin D was one of the top.

Yeah, well, I mean, it's a big deal because, you know, depending on the data you look at, up to 80% of us are insufficient or deficient. And the way the reference range works is it's based on a population measure. So you take a group of people, you measure you know, a spectrum of the levels in the population, and then you look at sort of what's the average, right? And you have like two standard deviations from that, and you can kind of determine what's, what's in quote normal. But normal is an optimal. If you were a Martian and you landed in America today, 75% of Americans are overweight. It would be normal to be overweight. It does not mean it's optimal. So the levels we often see in the laboratory ranges are not really where we should be hitting. The levels can be 20 or 30, but you should really probably have 45, 50, 60 at least. And I think, you know, probably 80% of us are deficient or insufficient. And that leads to depression, it leads to increase for Parkinson's, Alzheimer's, cancer, so many different things. And I think, you know, there's been mixed data about where placing it, fixing it or not. I think it's complicated because when you're like, you know, people are eating garbage and they throw vitamin D in there, it's not going to help. Yes, correct. If they're not exercising, they're smoking, they're drinking a lot, they're eating crap, taking vitamin D is not going to do anything. But in all things being equal, people who are low in vitamin D have higher risk of this and if you clean up your lifestyle and you're still.

Low in vitamin D, it'll make a big difference. Yeah, I'm glad you brought up context because one thing that very few people know, you could be spending as much time in the sun as you want, frolicking all day in the beautiful or even supplementing with vitamin D, but if you're not getting adequate magnesium in your diet, which 50% of the population does not get adequate magnesium, the enzymes that convert the vitamin D that your skin creates into its active hormone form in the body, all are magnesium dependent. And magnesium, half of us don't consume adequate magnesium. It's found in dark leafy greens, pumpkin.

Seeds, dark chocolate almonds. And a lot of things cause us to lose magnesium, stress, coffee, alcohol, sugar, all those things we love. Exactly, magnesium is like an anti-aging.

It's a macromineral, we don't consume enough of it and it's involved in all of the DNA repair enzymes. We're talking a little bit about DNA damage, they all require magnesium as a co-factor. It's involved in ATP synthesis, so energy production.

So true, I see so much of my practice and these patients come in with all these magnesium deficient symptoms, and they think I'm a genius when I give them magnesium, they go away. Things like migraines or headaches, constipation, muscle cramps, twitching, palpitations, anxiety, insomnia, anything that's irritable, twitches or spasms in any way, or cramps, is usually magnesium deficiency. And it's so easy when people take it, they go, my God, I didn't know I was so low. And I think you're right, it's so prevalent. I think as you age also your skin does doesn't really convert magnesium, I mean the vitamin D as well either, right?

Yeah. I make specific recommendations in the book for people no matter where they are in their life, no matter what age they are, it's important, you know, context is everything really, but you're right. People who are overweight, people who have darker skin complexions, people who are older, they probably are going to need to spend more time in the sun to create the same amount of vitamin D. Yeah.

I once learned from Michael Holick, who's a vitamin D expert. He said, if you really want to get adequate vitamin D without taking vitamin D, you have to basically be practically naked between 10 and 2 in the daytime for 20 minutes south of Atlanta.

Wow.

That probably isn't happening for 99% of people.

Yeah, it's tough. It's tough. I try to get into the sun as much as I can. Because the other thing about the sun, fun. We as humans, you know, we, I think that reductionist approach that we were talking about, it's, I think we're hardwired to try to break everything down. And I believe, I forget who it was. Maybe it was Michael Pollan, but in nutrition, they call it nutritionism.

Yeah.

Where they like to break down foods into just the bare Essentials to see if we can replicate it in a pill form.

And that hasn't, you know, really or identify or we even do worse. We sort of identify the bad ingredients like saturated fat or sugar or whatever. And so we focus on regulating those. food and then the food companies just kind of dial up or down different ingredients to sort of make it healthier, but it's not really, it's still junk food.

Yeah, exactly. And so I think we can apply the same thing to the benefits of getting sun exposure on our skin and in through our eyes. So, I mean, vitamin D is created when the UVB rays from the sun reach our skin, but UVA rays might actually be useful in terms of creating nitric oxide and actually helping us lower our blood pressure.

Yeah, that's pretty Yeah.

So blood pressure is another topic that I talk about in the book because it's so related to brain health. If you want your brain to be performing well, if you want it to age well, you really have to make.

Sure that your blood pressure is in a healthy range.

And getting the right amount of sunlight can help.

Can help. Yeah. Getting the right amount of sun. Now, you know, mental health is such a big crisis in this country. One in four people experience major depression in their life. It's the biggest cause because of the economic burden of chronic disease, not from direct health care costs, but things like disability, loss of quality of life, not being able to function very well in your life. And vitamin D is one of those things that seems to really impact depression. So you talk about a study in the book that has to do with vitamin D and depression. Can you talk more about that?

Well, vitamin D is important for the synthesis of serotonin, which is a neurotransmitter involved in mood A lot of it's a happy chemical. It's a happy chemical. That's what Prozac does, it increases serotonin, right? Increases serotonin, SSRIs selective serotonin reuptake inhibitors can boost serotonin at the synapse, which is serotonin is also involved in focus and attention and executive function. But yeah, so vitamin D is important in the synthesis of serotonin from its raw materials, one of which is tryptophan, an amino acid. So making sure that your vitamin D levels are in a normal healthy healthy range, important. And, you can easily get your vitamin D levels tested from a doctor. It's a very cheap test. The recommendations that I make in the book are to make sure that your levels are somewhere between 40 and 60 nanograms per milliliter, which seems to be a range where we see the lowest risk of all-cause mortality.

Yeah, I mean, I remember reading a study that was incredible. Women who had vitamin D levels less than 45, had a 60% higher chance of having preterm labor. And when you think of the cost of neonatal intensive care and taking care of preterm babies, it's staggering. And you're talking about pennies for a vitamin. Yeah. It can literally prevent preterm labor. So it's really connected to almost everything. And the, the differences with vitamin D is that not everybody needs the same amount. Right. So what should we be Correct.

Not everybody needs the same amount. Before you start taking vitamin D as a supplement, you ought to get your levels tested. When we synthesize it from the sun, our skin basically makes what we need and it breaks down the rest. It's almost impossible to get too much vitamin D from the sun.

Although lifeguards can have levels of 150.

That's amazing.

And that's not toxic.

Right, I mean it could increase, it increases calcium absorption. So I always like to recommend vitamin K2 for people that are in, I mean especially at those levels. But with a vitamin D supplement, I think generally there was a research calculation that suggested that for the general population 2,000 international units a day would be ideal to get the average person to an optimal level. but people again have different, you know, people who are older might need to supplement more people who are overweight might need to supplement more to get the same improvement. And also, again, yeah, people who are.

Overweight tend to be low in vitamin D because it's a fat-soluble vitamin. So it all gets sucked into the fat and it doesn't get into their system that we need.

Yeah, it gets sequestered by fat tissue. The same also can occur with other fat-soluble vitamins like A E-K. Yeah.

I don't know if you read this morning. This morning, probably not, because you probably don't read the JAMA Pediatrics Journal every day.

Not pediatrics, no.

But I do. And I read this paper this morning that showed that women, when they were pregnant, took 2,800 units of vitamin D compared to 400, which is in the typical prenatal vitamin, that there was a dramatic reduction in the effects on, bad effects on bone when their kids are born. In other words, their kids, their babies had much higher bone density and then their risk later in life of osteoporosis was dramatically reduced. So, and that, you know, that's almost 3,000 units, which most doctors don't even think about recommending. And, and some people, you know, may need up to five or ten thousand if they're not good absorbers and there's genes that affect that. So people might need only a thousand, but I, I think a thousand is minimum for most people and, and it takes a about a thousand units to raise your blood level 10 nanograms per deciliter. So if you're 20, you need at least 3, 000 to get up to 50.

Right.

And, and then you can see how you do. But I think people need to measure it, they need to check it, and they need to make sure they're okay. And if not, take the right supplement. And not the, the kind that you often get from your doctor, I hate to say, which is vitamin D2, which is not an active form of the vitamin, but vitamin D3. And you can get that over the counter now, and you can get thousand units and others, but you want to.

Make sure you measure. Right? Yeah, I mean vitamin D2 is the plant-based form of vitamin D and vitamin D3 is the animal-based form. It's bioidentical to what we create in our own skin. So you always want to make sure that you're taking vitamin D2. I mean sorry, D3.

Okay, so there that brings up a sticky question. So it's usually made from lanolin and other things that you can get it from sheep and stuff. And they're fat. So what if you're vegan? What do you do? That's a good question.

I've vegan sources of vitamin D3. That's hard to get. Yeah, right. Yeah, it's just one more of those nutrients that you're just not really optimizing for. Yeah, and often people don't convert vitamin.

D2 to D3, and if you're a vegan, you want to make sure you're checking vitamin D3. And you can also check D2, so you might have a really high D2, but a very low D3. So it's important to make sure. I once took care of this Hasidic rabbi and he had a really bad thyroid problem. And I said, you really need to take this combination thyroid, but I don't know if it's okay. Why? He said, well, it comes from, you know, pig. It's a whole thyroid extract from pig. And it's not kosher. It's fine as long as it's for your health and as long as you're not eating it and it's a medicine, it's fine. So I thought that was very interesting perspective.

I don't know. So.

The other thing you talk about in your book, connected to this whole circadian biology and how we can reset our clocks, is this idea of when we eat. Because we often focus on what we're eating, how much we're eating, but we really don't focus that much on when we're eating. And there's a lot of interesting research lately on the when, on fasting, intermittent fasting, time-restricted eating, all kinds of ideas that people are having that extend lifespan, that reduce the risk for many diseases. So tell us more about the importance of when. Yeah, well it seems that there's this.

Eating paradigm that's emerging in the literature and it's being called early time restricted feeding. So basically eating an earlier dinner seems to be associated with improvements in blood pressure and blood sugar independent of weight loss. So a lot of people online will say that intermittent fasting is really only useful insofar as it has an ability to help us control the amount of calories that we consume. consume. But it seems to be the case that by not eating too late at night, because as I mentioned, light is a major time setter that the brain uses to know what time of day it is and optimize its processes accordingly. But food is another time setter, and it's a time setter for the periphery, for the clocks that are in our metabolic organs, in the organs of digestion and what have you. And so eating too late at night might actually negatively affect things like blood pressure, sugar.

So, people like do intermittent fasting or when we call time-restricted eating, they'll eat at noon and they'll eat to eight at night. Is that a bad idea? Should it be more like eight in the morning till four in the afternoon?

I mean, that might be ideal. The issue is that we're not waking up with the sunrise and going to sleep with the sunset like our ancestors might have used to do. We, I mean, wake up a lot later. We go to sleep a lot later. So, I think that to try to recreate the optimal eating paradigm for the bodies that we've inherited might be a futile effort. So the recommendations that I make are to not eat for an hour or two after you wake up, especially if you wake up with an alarm clock. Because the problem is a lot of people who wake up artificially with an alarm clock to wake up, get ready for work, their melatonin levels actually haven't properly... It's likely that their melatonin levels haven't come down.

That's why they could be groggy when they wake up.

Groggy but also less insulin sensitive. So if you're drinking a glass of orange juice or eating a bran muffin.

Or whatever, first thing in the morning.

You probably shouldn't do anyway for breakfast. That's not a genius breakfast, right? Well, your listeners are savvy and they're not eating like that, right? But I hope you're not. But no, I mean, that is a mechanism by which your blood sugar can stay abnormally high, whereas if you just perhaps are to wait an hour or, you know, and also a way that you can make sure that your melatonin levels have come down is again to get that bright light in through your eyes in the morning.

So eat light for breakfast.

Eat light for breakfast. Yeah, eat light, especially if you have to wake up early. And then to eat a, I mean, I would say that if you were going to eat a heavy meal, do it in the daytime and then eat a lighter dinner.

Of course you'll be wanting to take a siesta in the afternoon.

Yeah.

So the Spanish had it right, that's right?

Yeah.

I agree. I always said you shouldn't eat three hours before bed because your body's getting ready to repair and heal. If it's digesting, it doesn't do such a good job. And if you want to gain weight, the best way to gain weight is night eating. It's the best way.

Yeah.

And it's not because, here's the thing. Sometimes I have these confrontations with people in the fitness world who say, well, a bagel isn't magically going to be 200 calories at 8:01 PM. if it's only 100 calories at 8 p.m. And that's true. The calorie content of food doesn't change from one time to the next, but it might actually, the disruption of your body's circadian rhythm might negatively affect hormones involved in energy metabolism, in hunger. So eating late at night could actually make you more hungry the following day.

My favorite study I read when I wrote my book, Ultra Metabolism, 15 years ago, was they fed people the same calories in three meals over the day, or they fed them one meal at night and the ones who had the one meal at night with the same amount of calories gained weight. Compared to the other group, even though they eat exactly the same amount of calories.

Because it might reduce leptin, which is the metabolic throttle essentially, that dictates our resting energy expenditure. It might actually increase levels of ghrelin, which is a hormone involved in hunger. So these are all the indirect ways in which late night eating can actually make you gain weight.

Whether or not-- and leptin also actually causes reduction in inflammation.

It's anti-inflammatory. Yeah.

Yeah.

So the system that we've inherited is very complex, but there's a great way of expressing it that I was able to glean from my interview with Sachin Panda, who's one of the leading experts on circadian biology. At a certain point in the evening, you have to kind of consider the kitchen having closed. You know, when you go into a restaurant after an hour? It happened to me last night.

I was in Washington, D.C. and I went with my friend Congressman Tim Ryan. We tried to go at a Mexican place and it was like this healthy vegan kind of taco place and they were shut. Kitchen closed. Kitchen's closed. Yeah. You had to find some other place. Yeah.

So, I mean, if you just think about your body in the same way and, you know, it's a little bit of a term of art. You could digest anything at any time of day. Does that mean it's going to be optimal, not necessarily? So at a certain point, I would say give yourself an 8 p.m. or 9 p.m. cut off and say the kitchen's closed in your body and that's it, you know? You're winding down, you're getting ready for bed, you're not going to be as insulin sensitive. in the evening as you were during the day. Also, metabolism, especially when eating lots of carbs, can cause insulin to spike, which can negatively affect hormones like growth hormone. It can affect the way that your brain cleans itself up because of an interaction with insulin degrading enzyme, which we know dismantles the plaques that are associated with Alzheimer's disease.

Which is often called type 3 diabetes. it's basically diabetes of the brain. If you're diabetic, your risk of Alzheimer's is four-fold higher. That's 400% higher. That's staggering. It's a great-- We also talked about a couple other things that are really great for the brain, like exercise, which I think 80 plus percent of Americans don't get enough of. I know. So, what's the connection between brain health and exercise?

Well, exercise is such a big topic and a lot of people are talking about it. I just think that it's really important to underscore that exercise is-- you're always talking about how food is medicine.

Exercise is medicine. Yeah, I was just saying if exercise was an pill, it would be the most powerful drug ever invented.

It really would be. It really would be. So I'm a big fan of resistance training. I think this is something that not enough people are talking about. Women, I see, can be afraid of weight training. They don't want to get too big and too bulky. I've been trying to get jacked for 20 years. It's not easy. It doesn't happen overnight. Resistance training, going to the gym, getting stronger, building muscle. prioritizing protein at every meal, it's gonna cause a recomp of your body, essentially. And, I've been trying.

I started about 60 years old. I'm in the gym. It's Struggle Street, but I'm not struggling. I'm starting to like it. But I think it's working. I can see a big change in my body and I feel stronger and less pain and it's good.

Yeah. I mean, if nothing else, having more muscle on your body provides a sink for excess energy. energy for excess glucose, excess starch and sugar that's going to make its way onto your plate inevitably. As much as we try to abide by the blood sugar solution and others who have told us to really... I wrote that. I mean, great book. It's important to note that like a New York City apartment, and I know you know this, Mark, there's not a lot of place to store stuff. And that's especially true in the body of sugar. We have very limited, there's very limited options in terms of where we can store the sugar that we consume.

Muscle.

Muscle is one of those places. And by growing muscle, by getting to the gym, you provide a sink basically to soak up extra sugar that you might consume or starches or what have you.

That's good, because yesterday I went to a class called Yoga Sculpt, which is basically yoga with weights, which is hard as heck, but I told myself it was good for me. Max would be happy with me. I did that.

You're looking, you're looking lean. I mean, I got it, good, you know.

If you loved that last video, you should check out the next one for sure on getting to the root cause of all disease.

Alzheimer's is inflammation of the brain. Like Parkinson's is inflammation of the brain. So we have to do everything we can to recognize that, not necessarily.