Transcription
So, if you think about what the feeling of tiredness is, it is an amalgamation of all kinds of mental and physiologic signals. When we're talking about tiredness, we have to remember that there are different dimensions of it, right? Tiredness can be felt sort of mentally. For example, you can feel fatigued at the thought of doing something, like if you want to write a book or if you want to move. That's a really good one—it's like, "Oh man, I gotta move." If you really think about it, the thought of moving doesn't actually cost a whole lot of energy; it's not like you're actually moving. It's the very thought of it that makes you feel fatigued.
But we do know that tiredness is not just in your head. We know that there's a lot of physiology that has to do with tiredness. We know that tiredness is a measure of energy levels. For example, if I haven't slept in 24 hours, I'm going to feel really, really tired, and that has nothing to do with whatever tasks I need to complete or things like that. If I eat a really heavy meal, I'm going to feel really tired afterward, and that's actually physiologic in nature.
Now, what we're going to do is look at tiredness from a different angle, which is sort of the physiologic angle. This is oftentimes what people think about when they're talking about tiredness; they kind of think about, "Okay, there's something wrong with my energy levels, and what should I do about it?" So, what I'd love to do today is share with you all how I think about or organize looking at tiredness from a physiologic angle. How can we understand the physiology of tiredness?
A couple of quick disclaimers or perspectives: a lot of people will share or talk about basic science research as it relates to tiredness. People will say things like you can look at a study that looks at eliminating refined sugar from your diet and how that boosts energy levels. You can look at studies that correlate things like vitamin D with energy. There are all kinds of basic science studies out there that will say, "This stuff makes people more tired; this stuff makes people less tired." These are primarily studies that are done in a laboratory.
The tricky thing about any one of those studies is that it may not apply to an individual person. For all those studies that show that eliminating refined sugar from your diet improves tiredness, it doesn't make tiredness completely go away for everyone in the trial. Some people actually get no benefit from eliminating sugar; other people get some benefit from eliminating sugar; some people get a lot of benefit from it. What we do in science is average all those things together and then come up with a conclusion.
Generally speaking, what I have found works almost better as a clinician is that when you're working with real human beings, there are a bunch of different solutions. But trying to figure out where to start—should I eliminate gluten? Should I eliminate dairy? Should I eliminate eggs? Should I do keto? Should I do intermittent fasting? Should I wake up every morning at 5 a.m.? Should I go swimming? Should I do resistance training? Should I do yoga? Should I do tai chi? Should I do Qigong? Should I drink this special kind of coffee? Should I add this supplement to my diet?—there are a thousand different things, and the answer to all of them is yes. You'll find someone out there who will talk about a paper and say yes to all of those things.
But practically, as a human being, what do you do if you are tired all the time? What I'd love to share with you all today is an approach to tiredness that incorporates all of that stuff. When I think about tiredness, I think about two buckets, and this is what I've learned from working for years as a psychiatrist. There's the circadian bucket and there's the metabolic bucket.
You may say, "Okay, what do you mean by circadian?" Our body goes through various cycles throughout the day. We feel more tired at night; some people feel tired in the morning. People have trouble getting out of bed; people have difficulty with sleep. So, there's a lot of tiredness that has nothing to do with metabolism, has nothing to do with energy, but has to do with cycles and sleep and things like that. By energy, I mean ATP generation; I don't mean the subjective feeling of energy because there's a lot of stuff that will subjectively make you feel tired and is kind of related to the circadian stuff.
This is where I think about things like sleep, daily cycles, afternoon crashes, and difficulty waking up in the morning. So, this is the circadian bucket. We're going to talk about all that stuff. In the metabolic bucket, we've got different stuff. Let's not worry about the sleep and stuff, but the other big dimension of tiredness and energy levels is what you put into your body and how your body responds to that.
The key to happiness is whatever is in the link in the description; check it out. This is stuff like homeostatic balance, blood sugar, nutrition, and things like nutrient deficiencies. But there's other stuff going on with metabolism as well, like inflammation. This is where all the stuff of, "What should I eat? When should I eat it? What effect does the food that I put into my body have?" That's the metabolic stuff, which is completely different from the circadian stuff.
As a clinician, when someone comes into my office and says, "I'm tired," there's also a psychological component or spiritual component. You may say, "What do you mean there's a psychological component?" The psychological component is in terms of tasks that just make you feel tired; it's up here; you just don't want to do it. Spiritually, some people come into my office and say, "I'm tired," and what they really mean is, "I have no zest for life; everything just feels like a chore."
Then what happens is if they try to fix their sleep schedule, that's not the problem. The problem is that they've got nothing to look forward to during the day. They can take as many supplements as they want to, but that's not going to fix it because it's not a metabolic problem. This approach is almost like a differential diagnosis standpoint: what's the differential diagnosis of feeling tired? It can be physiological, psychological, or spiritual.
In the physiology of it, there's the circadian branch and the metabolic branch. So, let's talk about the circadian branch. Let's start with simple stuff, and that is the pathology. There are all kinds of things that can mess with your sleep. At the top of the list is sleep apnea. Sleep apnea is a condition that probably affects somewhere around 5 to 8 percent of people in the world. Shockingly high, it results in periods of cessation of breathing during sleep. Essentially, what you do is drown or choke in the middle of your sleep. As you drown or choke, you don't get oxygen in. Then what happens is you start to drown physiologically—that's the best word, right? You're not getting oxygen, so for 60 seconds, you're going to have no oxygen.
Then what it does is trigger a survival response, a rush of adrenaline. You kind of reset your breathing apparatus, and you start breathing again. But the problem is that the rush of adrenaline and physiologic response is going to make you feel exhausted when you wake up in the morning. Think about what's happening: imagine if you were thrown overboard and were underwater for 60 seconds before you came up without a breath. Imagine how exhausted you would feel after that. People will have 20, 30, 50, 60, 100, or even 120 apneic episodes per night. So, physiologically, when you wake up, your body is ragged. That's sleep apnea.
There are other things that we'll talk about; there are other diagnoses that you can have, but circadian rhythm disorders are other examples. You can also have stuff like narcolepsy and things like that, but we're not going to talk about that. Circadian rhythm disorders are actually quite common. What these kind of mean is if we think about a regular day, right? Let's say there's midnight, 6 a.m., noon, 6 p.m., and then midnight. If we think about the activity level over time, most human beings' activity level is kind of like this: you wake up at maybe 6, you go to work by 9, work until 6 p.m., and wind down to sleep by midnight.
Now, the problem is that some people's circadian rhythm is actually more like this. What that means is that they're very exhausted when the rest of the world is working. When everyone else goes home for the day, they're just getting started. Between 12 and 4 a.m. is actually their maximum productivity. If your body's clock, which is what a circadian rhythm is, is off-center from the rest of the world and you force yourself to wake up at 6 a.m. like everyone else, this is your experience of life.
I want you all to think about this: let's use calculus and calculate the area under the curve for someone with a circadian rhythm disorder. This is the total amount of energy that they have during the day compared to a normal person. You look at "normal" people and you're like, "Wow, they're able to do so much," and you look at yourself and you're like, "I'm exhausted all the time; I can't do anything." That's because you've got a circadian rhythm disorder. You can actually do the same amount; it's just that you're jet-lagged compared to society.
There's also all kinds of really interesting research, for example, the circadian rhythm of teenagers shifts later. There's data that shows that if you start school at 9 a.m. or even 10 a.m. instead of, say, 8 a.m., teenagers will do a lot better because their circadian rhythm changes. Why does their circadian rhythm change? Because they're going through puberty and growth spurts, and our body physically grows while we're asleep. I don't know if you all have noticed this, but our body does a lot of growing when we're teenagers.
There's even data that shows that schools that start super early for teenagers—those kids do worse in all kinds of different ways. So, there can be circadian rhythm disorders. Part of the problem with circadian rhythm stuff: let's talk about solutions for a second. One is if you've got sleep apnea, the solution is actually medical care. There are these things called CPAPs (continuous positive airway pressure). They're different medical devices that you can use that will keep you from having apneic episodes overnight. You just have to get medical care for that.
If you're worried about, "How do I know if I have sleep apnea?" I can't diagnose you all over the Internet, unfortunately, but a really common sign of sleep apnea is waking up in the morning despite sleeping enough. If you went to bed and got eight or nine hours of sleep but wake up and feel exhausted, and it feels like you didn't get any sleep at all—you need 12 hours of sleep, 13 hours of sleep—you should probably talk to a doctor about that.
Another really common sign of sleep apnea is snoring. Part of the reason that you will become apneic is sometimes we have our soft palate and our epiglottis and some of the stuff in our oropharynx literally clamp down and prevent us from breathing. It will block our airways from this oropharynx area. We also know that, for example, having a lot of mass around here—if you've got a really thick neck or obesity—can increase the risk of sleep apnea. So, even weight loss can be a treatment for sleep apnea, depending on what the physiology is.
If you snore a lot and feel very tired in the morning despite getting a full night's sleep, public service announcement: talk to your doctor about it. In the case of circadian rhythm disorders, things are a little bit more complicated. Part of the reason that I think we have circadian rhythm disorders increasing in our society is that we aren't quite as bound to the sun and the moon as we used to be. This doesn't mean we're Druids or we're no longer Druids; this means that literally we have—this is where all the blue light kind of stuff comes in.
Blue light suppresses melatonin production. This is the right symbol from the pineal gland, and melatonin helps us sleep and keeps us on schedule, which is why people will use melatonin to adjust for jet lag. What we've got is that we'll take melatonin to help us get on a good sleep schedule, but here we are using blue light and technology that actually does the opposite of taking a melatonin tablet. It shuts off melatonin production.
This kind of stuff—the availability of the Internet—you may say, "What do you mean by that?" It means that at midnight, I want you all to imagine 10,000 years ago: what could you do if you were a human between the hours of midnight and 4 a.m.? What could you do? Nothing. Everyone's asleep. But now we have all kinds of stuff to do. There are 24-hour eateries; we can get food brought to our doorstep. There are going to be some degenerate noobs queuing at 3 a.m. for whatever game you want to play.
There are all kinds of things you can do, and that all interferes with your circadian rhythm. It allows you to get circadian rhythm adjusted; you can become an absolute degenerate when it comes to your circadian rhythm. But it turns out that aside from these kinds of things, there are a couple of other things that people don't realize about circadian rhythm.
The first is that your circadian rhythm is a natural cycle and that there are particular times of the day where you're good at particular things. This isn't actually what the circadian rhythm looks like; what the actual circadian rhythm looks like is probably like this. This maybe is like 9 to 10 a.m.; this is noonish, noon to 3; this is like 4 to 7; and sometimes this is like 9 to 11.
If you actually look at our activity, we actually have fluctuations in our activity, and this is conserved throughout the mammalian kingdom. If you look at the idea of a siesta or a nap in the afternoon, even in some countries in Europe, things will shut down around 2 p.m. and then open up again in the late afternoon. If you look at most mammals, like monkeys, they are awake at 5 a.m. or even earlier, and then they kind of chill out around 10 and are quiet during the hottest part of the day. Then around dusk, they become active again. The same is true of gazelles and impalas.
Humans are probably the same way. There's even some evidence that cognitive activity between the hours of 4 and 6 a.m. is very productive. If you look at religious traditions across the world, they all wake up and pray or meditate at 5 a.m. Why do all the religious traditions do that? It turns out that there's probably a circadian rhythm; there's something about our mind that is more at peace at that time.
The other really interesting thing is that I'll work with some people who think they're night owls, and then I'll ask them, "What do you mean? Help me understand the details of what you mean by your night owl." They'll say, "Well, I get started kind of sometimes around midnight, and then at 4 a.m., sometimes I'll do my best creative work. I'll write music; I'll write prose, poetry; inspiration comes at like 3 in the morning, 4 in the morning," which is actually consistent with our circadian rhythm.
So, it's not that they're night owls; it's that they're like morning people—like really, really morning people, early morning people—which is consistent with most of the mammalian kingdom. Another consideration for circadian rhythm, which a lot of people forget, is that we have these things called sleep cycles. If you look at sleep, it's stage one to four sleep, and then we have REM sleep after that.
What people don't understand about sleep architecture is that you basically go through these five stages. The problem is that different stages of sleep do different things for us. At the beginning of the night, let's say this is stage one sleep, this is stage two sleep, this is stage three sleep, this is stage four sleep, and this is REM sleep. At the end of the night, stage one is short, stage two is short, stage three is short, stage four is a little bit shorter, and REM sleep is actually really long.
The longer you sleep, the more your brain changes what stages it spends its time in. You'll actually go through a sleep cycle where you'll go through all five of these, and then you go through them again. Then you go back to stage one sleep. One thing that people don't realize is that if you wake up in the middle of a sleep cycle, you will feel really groggy.
I don't know if this has ever happened to you all, but you may find it kind of weird. If I sleep eight hours, I will feel tired when I wake up. If I sleep eight and a half to nine, I'll feel really good. Or if I sleep four hours or six hours, I'll feel really good. It's easier for me to wake up with six hours of sleep than it is for me to wake up with seven to eight hours of sleep. If you all have ever observed that, it's really weird. I'm actually getting less sleep, but I feel more rested when I wake up, and it's because you have to wake up during the right time of your sleep cycle.
Then you won't feel groggy. If you wake up in the middle of your sleep cycle, it's going to be a mess. This is also why the progression of sleep staging is really important. We know that a lot of the good stuff in sleep happens in REM. To this day, if anyone tells you they know exactly what's going on in our brain during sleep, they don't know what they're talking about because no one really knows.
Pay attention to your sleep cycles and recognize that you may not need eight hours of sleep. How did we get the number eight? Eight hours of sleep a night is what doctors recommend. What they did is they took a thousand people and asked, "Okay, who here is healthy?" and these four people raised their hands. Then they asked them how much they sleep at night. One person said ten, one person said eight, one person said seven, one person said 7.5. They averaged all these numbers together and decided, "Okay, 7.5 is the healthy amount of sleep that you need."
This is really weird. If we used this system to make clothing recommendations, everyone would wear gray smocks that were medium to large. We're like, "Okay, Doctor, what should I wear today?" and they're like, "Well, let me ask 10 people what they're wearing, average their sizes, average their colors, average their cuts, and that's the answer." This is how we do medicine; this is how we do basic science research. We just average a bunch of people together, right?
So, when we look at daily caloric intake, how did we get that number? We got it the same way. Why is it 2,000 calories a day? Well, we just asked people who are healthy how much they ate, and now you have papers that come out showing that mild calorie restriction, like 1,800 calories a day, actually leads to better health outcomes over the long term. It turns out that the number we got by just averaging all the crap together turned out to actually not lead to the best health. Fascinating! Who would have thought that if you just ask 10 people what works for them and average it all together, that's not actually the right answer for what works for you?
Okay, so be aware of waking up in the middle of your sleep cycle and remember that one of the reasons you may be tired from a circadian standpoint is if you're not getting enough sleep progression throughout the night. We don't want to just sleep with a low amount of REM sleep, but we can't. It's not like the first two hours of sleep and the last two hours of sleep give us different benefits.
Now, a good way to transition to metabolism is by talking about caffeine. So, what does caffeine do? The simplest way to describe what caffeine does is that it suppresses adenosine receptors in the brain. We have this thing called ATP, which is our basic unit of energy in our cells, and when you use up ATP, you end up with an adenosine byproduct. This is like when we have very high levels of ATP; this means that we have lots of energy. When we have high levels of adenosine, this means that we've got low energy.
What we have is something that measures this, so we're measuring our adenosine to ATP. That doesn't oversimplify. What caffeine does is it blocks the signal of low energy. It does not actually give us energy; it just makes our body numb to energy or the lack of energy, right? It's like the equivalent of taking medication that suppresses our hunger or suppresses our thirst. That's analogous to what caffeine does. It numbs our body's ability to detect fatigue, which is why we feel more energized, but we're not actually energized.
It also does other things, like increasing heart rate, for example. It increases our pulse, so we get kind of amped up. You can sort of get the jitters with caffeine, right? It does all kinds of other things, but this is where a lot of people will combat this kind of stuff, like sleep apnea, with things like caffeine. When I have patients who have sleep apnea, sometimes I'll ask them, "Do you feel tired in the morning?" They'll be like, "Yeah, absolutely." Then I'll ask them, "Okay, what do you do when you wake up?" It starts with two cups of coffee. I'm like, "Wow, okay."
Now this person has two things going on: not only do they have sleep apnea, but now they're blocking all of their energy signals. What happens is they don't actually take rest when they need to, so then they start running their car on empty, which creates all these other problems. Generally speaking, a lot of people like caffeine. There's some evidence that shows that a moderate amount of caffeine, which may have more to do with the other things in caffeinated beverages, like green tea or coffee, has all kinds of phenols and other things that probably have positive health benefits.
A moderate amount of caffeine intake per day can actually be fine or even healthy. But what you've got to be really careful about is if you're tired and you're drinking caffeine, especially if you're drinking a lot of caffeine, chances are what's happening is that the caffeine is suppressing your body's ability to detect fatigue, and so you can't take care of it the way that you should.
As an example, caffeine also suppresses appetite. One of the reasons why people like it if they're doing intermittent fasting is that if I'm using an appetite suppressant and I'm running on a caloric deficiency, that's going to cause my energy to crash. We use caffeine to feel less tired, and we end up making ourselves more tired because of all kinds of other things.
So, let's move on to the next thing on metabolism, which is glucose balance. Remember, it's an appetite suppressor, right? So, here's what we've got to understand about glucose balance. We've got two hormones: insulin and glucagon. There's basically a balance between these two things. Insulin is an anabolic hormone. What does anabolic mean? Anabolic means it builds things up. So, when we have high levels of insulin, we've got a lot of available energy, and we're going to use that as storage or building stuff like cellular machinery.
Generally speaking, when we're doing this process, our energy is not there to be used for activity; it's there to store away and build up machinery. If you all play games like RTSs or turn-based strategy games, insulin is like your expand hormone. It's like, "Okay, we're not going to build military units; we're going to boost up our economy." So, we're going to invest our resources in having more resources later.
But what this actually does is make us feel tired. Insulin makes us feel tired and actually activates the parasympathetic nervous system. What does the parasympathetic nervous system do? It rests and digests. This is also responsible for food comas. Now we're going to see a very common thing that we're seeing now more and more with the digital generation, which is, "I'm a starve myself for a while because I'm drinking caffeine and I get distracted by technology, and then I'm going to get so, so, so hungry that I feel super, super hungry. I'm going to eat a ton of food. I'm going to eat like 1,500 calories in one meal."
It's going to lead to a surge of insulin, and the surge of insulin is going to put me into a food coma, and then I'm going to feel really, really, really tired. Now we understand how improper sugar balance can lead to feeling tired. There are all kinds of other things to keep in mind here. Now we get to see a lot of why a lot of the healthy things that people are touting work.
The first thing is that a low-carb diet leads to low insulin levels. The trigger for insulin is carbohydrates. You can eat a ton of fat and protein, and your insulin levels will still be low. What this sort of means is that if we don't have activation of the parasympathetic nervous system, people are going to feel less tired. If you talk to people who are on ketogenic diets, they'll say, "Yeah, at the beginning it was rough, but now I have so much energy throughout the day. My energy level is actually way higher, and I feel way better."
Why is that? It's all mediated through insulin. So now we can see why low-carb or keto is pretty good. The next thing that we're going to talk a little bit about is intermittent fasting. If you look at things like fasting, it has its own whole situation going on, but let's talk about that very quickly. The first thing to understand is that we have glycogen, which is essentially our sugar stores, and they last about eight hours. After we run out of glycogen, we start burning fat, even breaking down protein, and then we're going to turn this; we're going to use these to generate glucose.
We're going to make sugar because we've run out of our sugar stores. For example, the brain requires sugar or ketones; it can't use other forms of energy like fats. So, we have to make glucose. The thing is, converting sugar to fat is very efficient; converting fat to sugar is very inefficient. The efficiency of this process is, I'd say, less than 10 percent—1, 16, or whatever that is. It's like 6 percent efficiency or 5 percent efficiency; let's say 6 percent efficiency.
What that means is that when people live in such a calorie-dense society, in order to be healthy, what we need to do is start really inefficiently burning calories. Imagine for a moment what your life would be like if instead of needing 2,000 calories a day, you needed 12,000 calories a day. If you're really, really inefficient, then you could eat all the hamburgers and crap that you want. The problem is that we're not that inefficient; we're actually quite efficient, which means that when we eat 2,000 calories, we're going to gain weight.
At 2,100 calories, 2,500 calories, we're going to gain weight. To counter that, what we need is some of these things like intermittent fasting. The reason that intermittent fasting is so good is that we run out of our sugar stores, and then for the next eight hours, we're in this state, which is actually the first state of starvation. We're in the early stage of starvation, and we're burning fat very inefficiently to maintain our glucose levels, but this causes us to lose weight.
Then we get to the third thing, which is inflammation. When it comes to what to eat and your energy levels, there tends to be all kinds of crap that causes low-grade inflammation. Examples of things that cause low-grade inflammation include obesity, gluten, dairy, eggs, and all kinds of minor food allergies. Now note that this is not celiac disease; celiac disease is a true allergy to gluten.
But there's even a very interesting case that I've worked with people who are like this. They will feel really, really bad if they're eating gluten. They cut out gluten, and then they start to feel more energetic, and they start to feel better. They have more energy; their mood is improved, things like that. The really interesting thing is that there is one guy in Austin, Texas, who uses a strain of wheat that is a thousand years old.
He's somehow found some kind of wheat that is grown somewhere, or he grows it himself. This strain of wheat has not been modified or selectively bred for the last thousand years. I know people who have gluten sensitivities who can eat wheat from his bread and be totally fine. Something about the way that—because if we look at it, gluten sensitivity is increasing. Why is that? What else has happened? Why are human beings suddenly becoming so sensitive?
When we talk about sensitivity, what we're talking about is that there are actually particular proteins in gluten that trigger an immune reaction. So, what's changed over the last thousand years? We've selectively bred wheat, even to the discovery of dwarf wheat, which is a Nobel Prize-winning discovery because we conquered world hunger with the discovery of dwarf wheat. That's probably some kind of chemical change that triggers some kind of immune reaction in some percentage of the population.
So, these low levels of inflammation also come from things like processed foods, and there's all kinds of other stuff. Refined sugars will cause inflammation; all kinds of stuff causes inflammation. The data is really unclear on how much stuff causes what percentage of inflammation in what percentage of human beings. You've got some people who are super into natural and anti-GMO and stuff like that. They think that GMO is the worst thing in the world, right? Natural is better, and there's probably some evidence that some of that's true. Pasture-raised is better than farm-raised, and this and that—there's probably some benefit to that, but we don't really know how much.
When it comes to the metabolic stuff, reducing these low levels of inflammation is key. There are other things that we also know, like eating fresh fruits and vegetables reduces inflammation. You may say, "How does this reduce inflammation?" It all has to do with gut bacteria.
So, here's what happened: in a quick summary, let's say a human being 50,000 years ago had a certain diet. This is the diet of the human being 50,000 years ago. The human being develops a symbiotic relationship with bacteria, and we developed this relationship for 50,000 years because the bacteria helps us digest these things. Since we've lived with this bacteria for a very long time, our immune system thinks that this bacteria is a good dude. "Hey, these are friendly bacteria; we do not need to kill them; they're not threatening."
Meanwhile, over here, there's another bacteria, and this bacteria causes, let's say, anthrax, and anthrax hurts us. When the immune system sees this, it's like, "This is a bad dude; let's kill it." Now, as our diet changes to just circles, we start to select for a different kind of bacteria because that's the bacteria that can digest just the circles.
Now, the problem is that this bacteria is different from this bacteria, and our immune system looks at this and is like, "Well, it's not really bad, but it's not very good; it's not a friend; it's kind of sus." This leads to inflammation. What we see is that when people eat foods that we've been eating for a long time, it tends to reduce the inflammation in the gut.
So, what this kind of comes down to—oh, there's also other things. Exercise is not something that we talked about, but exercise affects insulin metabolism in a very positive way, sugar metabolism, so it sort of fixes this. It also affects the kind of food that we crave.
Right? So, I'll ask you all a question: who here likes to have a milkshake with a burger and fries? If you enjoy having a milkshake with a burger and fries, raise your hand. Who here, whenever they exercise for an hour, craves a milkshake at the end of the hour? Right? When you exercise, what kind of stuff do you crave? You can feel really, really, really hungry. Most people just want to drink water.
So, exercise helps with all this stuff too. If you're tired, a couple of things: what do we do if we're tired? The first thing is pay attention. This is also where complex carbohydrates come in. Eating a cookie and eating a piece of fruit is going to be different because complex carbohydrates have something called a lower glycemic index, which is the amount of insulin that is released in response to this food.
If I eat an apple, this is actually not going to lead to a very big insulin spike. If I eat a grape, that's going to lead to more insulin release. If I eat a cookie, that's going to release even more insulin. If I eat a white flour cracker—not a whole wheat flour cracker—that'll lead to more insulin. Generally speaking, the higher the glycemic index of your diet is, the more tired you will feel.
Number one, you can also do intermittent fasting or a ketogenic diet. Sometimes people will do both. Whatever. Now we understand why these things will make people less tired. The other thing is to eat fruits and veggies because fruits and veggies have a really interesting thing. When you eat high-fiber diets, what ends up happening is—I don't know if this kind of makes sense to you all—but if you're starving and you eat an apple, you're no longer starving, but you're still kind of hungry.
But you can't really gorge yourself, right? If I'm really, really starving, and I don't know if this kind of makes sense to you all, if I'm starving, if you give me 1,500 calories that are packed very densely, I can eat them if I'm really, really hungry. But if you give me an apple first, and let's say an apple is like 180 calories—let's call it 200 calories—after eating the apple, I'm not going to eat a 1,300-calorie meal. I'm going to eat like a 700-calorie meal. Does that make sense?
Oh, Gaw RL is raiding with a party of 279. Thanks for the raid! We're talking about metabolism. I don't know if it's the most exciting topic. Is it 200? So, that's a good question. There's so much to learn. That's because our hunger—people are asking, "Okay, why doesn't an apple make you feel full if it's not only calories?"
Our perception of hunger is an integration of all kinds of circuits. It's an integration of our blood sugar, but it's also an integration of things like mass in the stomach. This is why stretch receptors—how much our belly is stretched and how much weight is in there—correlates with our hunger. This is why people will talk about rice cakes being pretty filling. They're super low-calorie, but they have some volume.
I don't know how much they actually create stretch in your stomach, so I'm not really sure if this is a great example. But if you eat some low-calorie dense food that has a lot of volume, you can't eat very much of it. You can eat 1,500 calories in one burger, but I don't know that you can eat 1,500 calories of broccoli, right? You just can't do it. Physically, you're not going to feel hungry. It'll be like eight heads of broccoli. The stretch receptors are going to be like, "Enough." Does that make sense?
There are also different kinds of hormones at play here, like ghrelin and leptin. So, if you're tired, pay attention to the glycemic index of stuff. By all means, reduce your carbohydrate intake or be careful when you eat.
Going back to this, let's integrate all this stuff. Let's say that you wake up at 5 a.m. Usually, when I wake up, the first thing in the morning, I don't eat something because I find that if I eat something right away, I get an insulin spike, and I'm not very productive. So, if I wake up at 5 a.m., I'm going to go two hours—maybe I'll have tea—but I'll go two hours without any food. Then I feel very hungry.
So, between 7 and 8, I'll eat a meal, and I'll usually have a pretty heavy meal. For example, today I had two breakfast tacos. The thing is, when I have two breakfast tacos, I know that I'm going to need enough calories, so I do this on purpose.
So, I know that—actually, today I woke up at 7; it's different with kids. So, let's do this, actually. If I eat at 8 o'clock, between 8 and 10 a.m., I'm not going to be very productive because now I'm going to be digesting. So, this is my digestion phase. I'm not going to do much work. Then I'll kind of get a second wind. Sometimes I'll even take a nap here.
I'll share with you all an interesting technique: one of the best ways to avoid post-meal fatigue is to lay down on your left side for 20 minutes. So, I'll lay down after I try to have a decently heavy meal. I'll lay down on my left side for about 20 minutes and close my eyes. Maybe I'll doze a little bit; I won't actually sleep.
So, let's say 10:30 I wake up. Then I'm going to do some kind of random work between 10 and 4. This is going to be stuff like meetings, emails, and other kinds of low cognitive activity work. Then between 4 and 7, or sometimes between 7 and 9, I'll do more creative work, like writing or whatever. Then it's bedtime.
The key thing about maintaining your energy level throughout the day is that this afternoon crash is oftentimes if you don't eat enough for breakfast and you're starving at noon, and you eat very heavy at noon, you're going to have an afternoon crash. You're going to have an afternoon crash. Why? There are three reasons why you have the afternoon crash.
Number one, we're hungry because we rushed in the morning. Reason number two: we had caffeine in the morning. I wake up, I have my cup of coffee; it's an appetite suppressant. Four hours later, the caffeine starts to wear off a little bit. Not only do we start to feel that tiredness, but then this appetite suppressant makes us even more hungry.
Then we eat a really big meal. So, this plus this equals a big meal. Once we have a big meal, a big insulin spike makes us feel tired. Then what happens is, let's say two hours later—so six hours post-caffeine—the caffeine's really starting to wear off. This is going to make me tired. On top of that, it's now 2 p.m., and what do the monkeys do at 2? On top of that, roll in circadian rhythm. You're going to be more tired.
This is why people crash in the afternoon, right? Because everything aligns. If you say, "Okay, I'm tired in the afternoon; what should I do?" Well, you can do all kinds of stuff. One is you could just take a nap. The second thing you can do is eat something with your coffee. The third thing you can do is cut back on your caffeine intake. The fourth thing you can do is when you eat a big meal, make sure it's low carb. The fifth thing you can do is have a snack at 10 a.m. so that you're not starving when noon comes around.
The sixth thing that you can do—and I don't know if you all have done this—is have more coffee. So, I know we covered a lot of stuff, and unfortunately, if you're tired, it's not simple. If you think about what the feeling of tiredness is, it is an amalgamation of all kinds of mental and physiologic signals: insulin, leptin, ghrelin, inflammation, glycogen stores, fat stores, circadian rhythm stuff.
There's stuff going on in your brain, in your reticular activating formation, that is causing you to lay down or calm down or feel tired. Your vagus nerve is active or inactive, depending on what's going on. Even the way that you breathe will affect your fatigue level. People are struggling with tiredness; everyone's more tired.
Why is that? When I work with people, I tend to split it into two buckets: there's the circadian stuff, which has to do with your body's natural rhythms and how we may not be aligned with those kinds of natural rhythms. If we get interrupted sleep, or if we don't sleep enough, or if we sleep too much, we'll be tired the next day. In the most unlucky cases, what we're talking about is actual pathology, like sleep apnea.
So, the circadian stuff is kind of like sleep, but then there's another whole piece to this, which is metabolism, which is our actual energy level and how our level of fatigue throughout the day is going to be dictated by all these different kinds of metabolic hormones and sugar balances and stuff like that. This is why everyone will say, "Oh, I cut out gluten, and now I feel so much more energetic. I'm doing keto; I'm doing intermittent fasting; I feel so much better."
There are all kinds of physiologic reasons for that. What everyone is doing is saying, "Okay, so which one of these should I do? Should I do keto? Should I do intermittent fasting? Should I cut out dairy? Should I become vegan? Should I get one of those little watch things that monitors my sleep level? What should I do? Should I take melatonin? Should I take this supplement? Should I drink more coffee? Should I drink less coffee? Should I drink a special kind of coffee? Should I drink more expensive coffee?"
Everyone's wondering, "How do we do this stuff? What's the right answer?" I don't know how to say this, but if any of that stuff works super, super, super well, it would eliminate everything else from the market, right? That's what happened with antibiotics. If you look at the alternative medicine that's out there, there's very little alternative medicine for the stuff that we do really well with regular medicine.
Even people who are super into alternative medicine—these are a lot of my patients—if they get sick, they'll take a course of antibiotics because it works really well. There's a really interesting principle from the history of medicine that when there is one treatment that works, if you have 10 treatments for something, all of them don't work well. When you have one treatment that exists, that's because it works really well. It's just Darwinian; it's like the theory of evolution and natural selection.
So, you have all these thousand diets. In which one should you do? It comes down to these factors. It's not about one diet; it's not like this one is the thing that works. They all work to some degree. The question is, which one fits for you? What's your particular pattern of tiredness? Are you tired first thing in the morning when you wake up? What's your caffeine consumption like? Do you crash in the afternoon? Do you really hit your stride at 7 p.m.?
The more that you understand yourself, the more that you'll be able to leverage any of these individual things and figure out what kind of plan works well for you. If you found this video helpful, check out Dr. K's guide. We've spent hundreds of hours writing and filming to help people understand their mind so that they can build the lives that they want. So, check out the link in the description below.