Eating for Better Sleep & Foods that Improve Metabolic Health | Dr. Marie-Pierre St-Onge

what was it that they ate that day that impacted how they slept that night? And we found that higher intakes of fiber were associated with more deep sleep, higher intakes of saturated fat, less deep sleep, and then more refined carbohydrates, simple sugars, more arousals. You're not getting deep slowwave sleep, REN sleep as much as you would otherwise. Welcome to the Huberman Lab podcast, where we discuss science and science-based tools for everyday life. I'm Andrew Huberman and I'm a professor of neurobiology and opthalmology at Stanford School of Medicine. My guest today is Dr. Marie Pierre Strange, a professor of nutritional medicine at the Institute of Human Nutrition at Columbia University School of Medicine. Today we discuss how you eat impacts your sleep and how you sleep impacts what you eat as well as how your body utilizes food depending on how you slept. Now we've talked about food and we've talked about sleep many times before on this podcast. But Dr. St. On's work is unique because she runs one of the few laboratories in the world to look at the birectional relationship between sleep and food. For instance, you'll learn how even modest sleep deprivation increases hunger but differently in men and women. In men, it happens to increase the hormones that drive the desire to eat. Whereas in women, it reduces naturally made peptides such as GLP, which suppress hunger. Today's discussion gets into the specific actionable items that you can do to improve your sleep, and the way that your body handles food and hunger. We talk about the role of sleep in regulating blood sugar, cortisol levels, overall metabolism, and cardioabolic health. Now, because Dr. St. Oja's research focuses on sleep and nutrition, but she's also spent a significant amount of time studying how specific nutrients impact overall health and not just sleep. We also talk about that. I'm certain that you'll come away from today's episode with a lot of new information you haven't heard elsewhere, as well as with the intention to make small or perhaps even large changes in behavior and nutritional choices that the science tell us can significantly improve your sleep, your metabolism, and overall health. Before we begin, I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford. It is however part of my desire and effort to bring zero cost to consumer information about science and science related tools to the general public. In keeping with that theme, today's episode does include sponsors. And now for my discussion with Dr. Marie Pierre St. Dr. Marie Pierre St. welcome. Thank you for having me. Sleep impacts how and what we eat and how and what we eat impacts sleep. That's a different perspective than I think most people take. I think most people are familiar, however, with not getting the best night's sleep, maybe feeling like their impulsivity to eat quote unquote bad foods is a little higher, and then also hopefully familiar with having a great night's sleep and feeling like we're just kind of in control in a different way. Maybe you could just kind of share for us what's really going on beneath that experience and when subtle or not so subtle chronic sleep loss. So not an allnighter necessarily but you know 45 minutes less here 90 minutes less there etc etc how that plays out in terms of our nutrition and then we'll go in from the nutrition side to sleep. Sure. So there's a couple of questions that you have in there actually about the extent of sleep loss and how that influences your food intake, what we see in the general population versus what we do in a lab to address causality. So let me start with you know the population-based studies right. So when I started being interested in in sleep it was coming from an obesity angle. My PhD is in nutrition. I trained as a postoc in uh body composition obesity research and we were getting a lot of information from population based studies that people who sleep too little have a higher body mass index than people who get adequate amount of sleep. Then it became there is a higher prevalence of people with obesity in this short sleep uh group. Then studies evaluating changes over time seeing that people who don't sleep enough tend to gain more weight. There was a famous uh nurses health study that I really like to site uh when I give talks that was published in 2006 where uh they tracked nurses over 14 years and those nurses that reported sleeping five six hours had much higher rate of weight gain over that 14 15 year period than the nurses who had reported sleeping seven or eight hours per night. So those are observations that we get from largecale population studies, cohorts, but you know what they what those studies tell us is that things are happening at a point in time or may influence something that's happening over time but not necessarily that one causes the other. Right? So I started uh my work in this field trying to uncover whether sleeping too little actually causes weight gain. And so in my opinion because I was coming from a lab where I trained in the measurement of energy balance. So how much energ how much energy you eat versus how much energy you burn like well if sleep leads to obesity leads to weight gain it has to impact this energy balance regulation. So it's either that we eat more than we should or that we exercise less we burn less or we eat more or maybe it's a combination of the two. Let's try this out and and see. So my first uh my first study, my first NIH grant, the big RO1s, you know, was to look at exactly at this. So we had people who had adequate sleep and we brought them in the lab and we asked them in a crossover design. So half of the participants started out sleeping adequately. So they we gave them a 9-hour time in bed opportunity or we asked them to sleep too little. So, they had a 4-hour time in bed opportunity, very short, but we did this for five nights. And then we took all sorts of measurements in a controlled feeding condition. So, for the first three days, we told we had our participants eat the exact same thing regardless of how much time in bed they slept they got at night. And then we measured appetite regulating hormones. We did neuroiming uh to really get at isolating the impact of sleep duration on appetite regulating hormones and and um neuronal responses to foods. And then on the last day we let them self- select their food intake and we measured that in the lab. From that study we showed that in men specifically uh we saw an increase in ghrein in response to short sleep. So this hormone that triggers food intake in women we saw a reduction in GLP-1 interestingly enough glucagon like peptide one. So the satiety hormone was reduced as a result of short sleep in women. And then when uh we measured their food intake in the lab, they ate 300 calories more in the short sleep condition than they when they got their regular adequate sleep of at least 7 and 1/2 hours, a little more than that uh per night. Then uh you were asking about you know brain responses. Uh we looked at neuronal responses to food stimuli. We found upregulation in uh reward centers of the brain in the context of sleep restriction compared to the context of adequate sleep. So altogether really building a case that when you don't sleep enough at night, you have both physiological signals to eat more for men or not stop eating in women that lead to greater food intake. that's also uh could be impacted by just pleasurable centers that are activated to a greater extent as a result of uh insufficient sleep. Amazing this sex specific split in the data if I have it correctly that when men are sleepd deprived so getting four hours per night the signals that drive a pettitive desire to eat are higher in women it's more that the break uh on eating on satiety is reduced. Exactly. Okay. As far as I know, the GLP pathways are not um divergent by by sex, but of course I'm not deeply versed in that literature. Is there any evidence that GLPs are functioning different in men and women like circadian wise or anything like that or this just this was just a fertuitous outcome or I should say uh incidental outcome? This was an incidental outcome. We really didn't know what to expect. We didn't really know at all that we'd see sex differences. Mhm. Because there had been prior studies and prior studies had shown that ghrein was increased as a result of sleep restriction. They also showed that leptin was reduced as a result of sleep restriction. And when we got our data, if we analyzed our data with all of our participants together and there was no effect. Mhm. And that was surprising. And people would say, "Don't you know? Don't you know sleep restriction increases grein?" Like, well, I guess I don't know because in our study it doesn't. But then we saw these sex specific differences. Then it made sense then that in the full sample when we had an equal number of men and women we saw no effect on ghrein because there was no effect in women but there was an effect in men which was reproducing what others had found because all the prior studies had been done in men only. 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It's like kind of like central ache like you just and and I wonder a extent to which people eat to overcome like to kind of quell the the pain of sleep deprivation. Maybe people react differently to sleep deprivation. Maybe their subjective experience of it is is very different. But what do you think is happening in that uh in that short relatively short amount of sleep that's missing? What is getting reset? Is it neural? Is it endocrine? It's obviously all those things, but what do you think is the the switch that allows people to enter a a day in a in a much more healthy fashion or or a sick essentially in a slightly sick fashion? In our study, it was actually a 50% reduction in sleep because when they had 9 hours sleep opportunity, they slept around 7 and 1/2 and when they had the they were all people who we had screened to sleep at least seven measured by ectography. So, and on average they get 7 and 1/2. And in the sleep restricted condition, they got on average about 3 hours and 50 minutes. So, it's like staying up late working on a deadline then trying to catch an early flight. Yeah, it's pretty brutal. It's pretty brutal. And that was maintained, you know, they had five nights of that. So that five nights of that. Were they coming unglued mentally, too? That I think I would feel terrible after that kind of stretch that the end they were done. Like there was no way anyone would want to keep keep coming for that. But they were in the lab. They were under supervision the whole time. We didn't let them go out on their own. Uh so they were well supervised. Make sure that nothing uh nothing would happen to them. No naps. No naps. No. No. Uh but so what happens is I think there's some subconscious need to to eat more when you're sleepdeprived. There's also you know there's a thermic effect of of food, right? So it gives you a jolt of energy to eat something. People know that you eat it wakes you up in a way. You know, neuronal signaling that that enhances uh pleasurable and reward centers of the brain where you know when also fatigue sits in and now it's like do you really want to have this conversation with yourself about what to choose at the buffet table? you know, there's fatigue and uh and others have shown also that sleepiness tends to correlate with all of this that there's these triggers for more pleasurable food consumption with um with sleep restriction and it's been reproduced. There's been so many studies uh and they all you know agree to to the extent of overeating you know a meta analysis showed 250 to 400 calories of overeating which might not sound like much but when you start layering that in day after day and you think you know 3500 excess calories more or less for a pound of body weight and then you start when people accumulate that over time if they're in a night shift condition or new parents or tending to a sick relative were just final exams like it it's a real thing. It's a real thing. Uh Neymar Kovven in uh 2022 published a paper where uh they had sleep restriction about 5 hours per night versus 7 and 1 half hours per night for two weeks and participants gained half a kilo in a twoe period. So you do nothing and you just you know sleep less and gain gain almost a pound in two weeks. It strikes me that, you know, for a long time in the stress research, the idea was when people are stressed, they reach for kind of quote unquote comfort foods, carbohydrate, and typically starch fat, starched fat, sugar combination foods to comfort them. And and the the just so story was always that uh okay, well, you know, cortisol's main role is to deploy glucose, and so people are doing this as a way to bring excess energy and and it all kind of fits together. What is the relationship between these forms of sleep deprivation that you work on and stress? Is it really a way of of I'm not saying just inducing stress because I think sleep is its own thing, but it's stressful just to be less than adequately rested independent of the things coming at you in life, right? Is what you're studying stress. So if you're thinking about physiological stress measured by cortisol levels in that study actually cortisol wasn't changed in the short sleep. In the short sleep. Tell me more about that. I'm fascinated by circadian rhythms and cortisol. So what does what does that what does that mean? There was no difference between the two conditions. The adequate sleep or short sleep on cortisol levels for 5 days of sleep restriction at basically 4 hours a night. So cortisol is still peaking in the in the morning, still dropping in the evening. Yeah. Wow. That's very surprising to me. I don't know. I don't know if it's the context of you know being in a lab where everything's safe taken care of for them. there is nothing outside to aggravate this. So I don't know maybe when you're in the context of sleep restriction but also dealing with your daily life you needing to take care of your kids needing to get to work needing to do all the activities of daily living maybe then that becomes you know the the added stressful. So the message is if you suffer less than adequate sleep, get someone to take care of everything else. You better be in a spa. Exactly. Exactly. No, I and I'm not challenging the result. I just find it really interesting. I would have thought that basil cortisol levels would would go ary. Well, in that study also, we didn't see any effect on glucose or insulin. Nothing. Nothing. The curves were superimposable. while they were eating the exact same food at the exact same time, exact same quantity. The only thing we changed was the amount of sleep opportunity they got at night. So to me, this means that it's a combination of different things that causes the metabolic abnormalities that we notice in free living populations. People aren't isolated. They're not in a box where they're not sleeping enough and they're choosing to eat higher fat, higher sugar, higher salt, poor diet that then triggers a worsening and may be compounded by the lack of sleep, even worsening of of those cardioabolic outcomes because we did a follow-up study to this uh this severe sleep restriction study. So the reason why we did that was because exactly for this reason because we did not find any adverse impact on glucose or insulin or lipid profile. And we're like so what is it then? Why is it that in population based studies we find that people who sleep too little have higher risk of cardiovascular disease, higher risk of hypertension, higher blood pressure, higher uh risk of type two diabetes. So, because we had seen that food choices were different, that they ate a diet that was higher in calories, higher uh in fat and saturated fat, we thought maybe if you're in a free living situation, that's when you start to see those cardio metabolic outcomes because it's compounded by maybe uh more sedentary behavior and alterations in in uh food choices and and diet. So the follow-up study then was to recruit good sleepers, people who sleep at least seven hours per night, verified by ectography, who answer on questionnaires that their sleep quality is good. And then to take these people and say, "Okay, now you're either going to continue your excellent sleep or you're going to now go to bed an hour and a half later." So that you get an hour and a half reduction in sleep. Because when we screen people to sleep at least seven hours per night, they sleep about seven and a half. And reducing by an hour and a half gets to 6 hours, which is short sleep, insufficient on average what people who don't get enough sleep get. They're missing a full sleep cycle. Yeah, pretty much. and uh and they can sustain that for prolonged periods because that's what people report in in population based studies. And now when we did that, we saw that insulin resistance was increased after 6 weeks of sleep restriction compared to adequate sleep. We saw insulin sensitivity was reduced. It was worse actually in post-menopausal women compared to premenopausal women. We saw blood pressure uh was increased. Uh so those cardio metatabolic outcomes were adversely impacted in free living mild sustained sleep restriction for 6 weeks. 6 weeks was something else also. It was it was tough. I can only imagine. Wow. Okay. Because my mind always goes to all right. Well, we wake up in the morning because of an increase in cortisol. That's circadian. It's not related to sleep per se. It just kind of overlaps with the end of the night's sleep. If that's independent of sleep and cortisol drives glucose release, we know this. At least in the first study you described, glucose levels weren't altered. You said it was isocaloric, so people were it's not like they're eating more. No, they're the the hormones that are driving the desire to eat more are elevated. The didn't let them eat more, but you didn't let them. I think that's a a key thing that you you pointed out before, but I think we want to underscore. And then of course the GLP uh levels in women being reduced. It's not that then they were able to eat as we say ad libidum and then they happen to eat more but they gained weight. So what's kind of the action end of things that causes them to gain weight if they're basically in an isocchloric diet? And I have a I have a I have an idea what it might be but I'm curious what the answer is. Yes. I think they're they're more sedentary during the day. Less spontaneous activity. Right. less spontaneous activity because we also did a study to look at energy expenditure that's really difficult actually to measure in my opinion energy expenditure there's multiple components to energy expenditure uh but we did a study where this was a small study we enrolled only women for that and we have a metabolic chamber at Colombia that we were able to use for this uh so this small room in which we keep people and we measure minuteby at oxygen consumption and carbon dioxide production. And we were able to show that energy expenditure is actually increased in the context of sleep restriction in the metabolic chamber because it's more costly energetically to remain awake than to fall asleep. So energy expenditure when participants were awake was identical in both conditions regardless of how much sleep they got the night before. So it's fidgeting movement because we've talked before in this podcast about the non-ex exercise induced thermogenesis. It's a big number. I mean you people who fidget a lot bounce their knee a lot. I mean sometimes these people are burning 1500 calories more per day and everyone goes oh my god how could that possibly be? But I mean that's a lot. That's at the extreme. But it is kind of interesting to observe people out in the world and you sometimes see that people who are very very lean, very let's just say thin and lean nowadays, who knows because of the GLPS etc. But they tend to have a lot of spontaneous movement. They tend to stand up quickly. They tend to walk quickly. Well, you're from New York, so everyone there walks faster than out here. But it's a real thing, you know, whereas some people like me are kind of more middle of the curve, but you know, I sit a bit more still unless I'm very caffeinated. These things add up over time in ways that I think most people underestimate. Yeah. So for us it was about 5% of energy increased, but it it and it ended up being about 90 calories, nowhere close to the 300 calories that uh more of intake they got over over a day in the prior study. So it's still an imbalance towards a positive energy balance when we do the math but there is an increase in um in energy expenditure again in the confines of a metabolic chamber which you know for most people is equivalent of the size of their bathroom. Right. Right. You have like a bed, a table and a sink, a toilet. That's it. So you can't can't do much in there. But you can do studies quote unquote out in the wild with um acttometry or what? Yeah, excuse me. Yeah. Yes. A little while ago, I saw a study that said that if you are one night sleepd deprived, like you get one or two hours less uh sleep than normally you would get to feel rested that it's actually advantageous to exercise because it offsets some of the um increase in inflammation. But then if you're going multiple nights that way, exercising on a regular basis when sleep deprived, it just sets up a um susceptibility to illness, susceptibility to injury and so forth. How much of what you observe in the under the conditions of sleep deprivation do you think are downstream or upstream of this thing that we just call inflammation? like is this just like a bodywide response and there are a bunch of things that have gone ary and and so like a bunch of systems are disregulated or can we pinpoint okay when you're sleepd deprived this is what this is what's happening because I think if if women knew that their GLPs were down when they're down on sleep so that they should expect that they would feel less satiety if men knew that their ghrein levels were elevated when they're down on sleep that they're going to feel hung hungrier I mean we have pretty big prefrontal cortex most people anyway and we can intervene simply on the basis of knowledge. I think that's what's empowering and I think about this sometimes too when I'm when I'm thinking about you know my my diet at times right I'm like I do I really want to eat this or is it because I really didn't sleep last night right so you can you can make you can ask yourself these questions take a pause and say okay do I really want you know dessert or is it just that I'm tired and you know I should just I'm fine I don't need it Mhm. So if you if you step back and think that maybe part of it is because you didn't sleep well the night before, then you can make your appropriate choices, right? Say, "Okay, I probably don't need the the extra calories right now." Or or maybe you say, "You know what? I had a really bad night last night and those extra calories, I don't really care because they're going to make me feel good and I need some pickme up." But you know that's that's all the choices to make right you know because mood comes into comes into play as well. So well ultimately that brings us to the the other direction of the equation right how does what we eat impact our sleep. This is something that I think most people have heard about in the context of try not to eat too close to bedtime. Um this is an active debate in many households actually. Some people seem to be fine eating close to bedtime and sleeping and even if they track their sleep. Other people it really disrupts their sleep. I'm interested in both the timing of food intake relative to sleep but also the content of the food and how it impacts sleep. What's known about that either from your work or from other work? When we started this conversation, I was telling you about these population based studies, you know, cross-sectional data where two things happen at the same time and you, you know, you you don't really know causality, they happen at the same time. And I think early on uh in this field we started thinking about sleep as the promoter of food intake or as a sleepcausing changes in diet exercise but didn't really think that maybe it's the other way around or maybe the other way around is just as plausible. So I started thinking about that and said well what what if we took the other approach? What if we looked at diet and examined how diet influenced future sleep? And my first paper in this field was using data from the multi-ethnic study of atheroscerosis. It's actually kind of hard to find good cohorts that have good nutrition data, good sleep data, and data over over years. Right? So MESA multi-thnics of study of atherosclerosis is one of those great cohorts that we have in here in the US that has all of the above. So I paired up with a colleague of mine, Susan Redline in Boston and uh she's a principal investigator on their sleep ancillary study and we asked the question of diet quality and its impact on sleep duration, insomnia symptoms and we found that having a diet that more closely aligns with the Mediterranean diet was associated with better uh probability of having adequate sleep and reduced um insomnia symptoms in this cohort. So then it launched a whole field of study really to to keep looking at this and we've looked at this in different studies and different cohorts actually uh earlier this year we published data from the women's health initiative another large large cohort with good diet data and and sleep information. We took a really really nice approach in this uh longitudinal analysis. I don't know. Usually when we do longitunal studies, we exclude people who have the condition at baseline, right? So if you're trying to see this factor at baseline, how does it influence hypertension 10 years later, you usually exclude people who have hypertension at baseline? Because you want to see the development of hypertension. In this case, we're looking at insomnia symptoms. But insomnia is one of those conditions that's not necessarily static. It resolves, right? So you can have insomnia and then a few years later not have insomnia or you can not have insomnia now and develop insomnia. So what we did is we broke our down our participants into two groups. the people who had no insomnia at baseline and at three years followup participants who had insomnia at baseline but not at 3 years followup. So they were in the healthful sleep improving sleep and then the other group was all those women who had insomnia at baseline and at 3 years and no insomnia at baseline but insomnia at 3 years. So they were the persistent insomnia progressing towards poor sleep group. And we found that the women who had a diet that was more closely aligned to the Mediterranean diet. But we also looked at uh an American type of diet profile called the DASH diet. The dietary approaches to stop hypertension. Women who had a dietary profile closer to those two types of diets, healthful diets were less likely to have hypertension uh insomnia at three years. And the DASH diet is what? Dietary approaches to stop hypert hypertension was developed to uh reduce prevent hypertension, reduce blood pressure in people by increasing intakes of fruits and vegetables, nuts and seeds, consuming low-fat dairy, more plant-based types of uh diet and and can be has been tested in a low salt or regular salt profile. How did those work out? I'm just curious. Do you recall if the low salt high salt um condition there is salt sensitivity so there are some people who are very sensitive to salt and so having a reduced salt diet will really improve their blood pressure others not so much but the DASH diet regardless of its salt content did better than the equivalent non-dash which would be your average you know American diet whatever that is yeah higher in saturated fat and sugars which seems to be changing now because of the GLPS I I feel Like that's, you know, uh maybe that's a skewed perspective, but I feel like the the typical American diet is it might not be changing so much in content, but in volume it seems like people are eating less. Certainly the snack food companies, from what I understand, are struggling. Alcohol companies, that's a different issue, but there certainly have uh sales are way way down, but it just seems like people's appetites are down. Well, GLP1s will do that, right? Yeah. And we were talking about this the other day here. uh how many Americans have tried a GLP? The estimates are anywhere from like one in seven. Some people say it's it's more which is pretty incredible. Yeah, it's pretty high. But this is interesting. So how people eat impacts their sleep, I'm sure the listeners and I also am thinking okay but people who are eating a Mediterranean diet, right? olive oils, fish, you know, fruits, vegetables, they are probably more apt to walk more, exercise more, socialize more, all the how do you separate out the variables in a study like that? Uh well, so in population based studies, we adjust for a bunch of coariants, right? We have all these questionnaires that uh that are given out to people asking them about their race, occupation, sociodemographic stat, socioeconomic status, and then we adjust. We adjust for um different illnesses that they may have, depression, physical activity level. Um so we try to take all this in into consideration. Obviously we there's always unmeasured factors that you can't control for social interactions like you um you mentioned. It's usually not captured very well. It's not something that we uh we can adjust for. But one thing that we did in my lab uh going back to that original study was to look at uh how diet influenced sleep at night in the participants in our inpatient study. So we took the 9-hour time in bed opportunity phase only that one. In the 4-hour time in bed opportunity participants were very efficient. There was not much variability in sleep duration in that phase. They slept as much as they could in that 4-hour opportunity, but in the nine hours, there was variability there. Some people got more or less. So, we wanted to see if food intake was related to their sleep at night. That study, we had polynography assessments of sleep every single night. Like I mentioned, we had uh control diet initially and then we let them self- select their food intakes. So we took a very systematic approach to evaluating how diet could influence sleep in that study. We said first of all, was the diet that they chose different than the diet that we gave them? First step, right? It was. So they ate almost 450 calories more. They ate 33% more saturated fat. uh little less protein I believe a little more carbohydrates not much but it it was different so like okay so so there's difference between the diets okay now was their sleep at night different when they were eating the diet that we fed them compared to what they self- selected and it they it was different it wasn't different in terms of duration but it was different in time it took them to fall asleep which was over 70% longer to fall asleep when they self- selected their diet and their slowwave sleep. So deep sleep was shorter. I think it was about 23 20% shorter uh when they self- selected their diet compared to what we had given them. Was timing of food intake impacted? Because when I think of what impacts what reduces um slowwave deep sleep, it's eating too close to bedtime. Mhm. So we did not take that into consideration in that study. We didn't uh we didn't look at that. We had their their food intake profile and didn't specifically look in that phase when's when was their last eating period. But it could have been different than in the controlled feeding condition because in the controlled feeding condition they had set meals at specific times. But they all went to bed at 10 p.m. Then the other question was, okay, what was it that they ate that day that impacted how they slept that night? And we found that higher intakes of fiber were associated with more deep sleep, arousals. So when we talk about arousals in the context of polyynography, it doesn't necessarily mean full-on waking up or awakening, it really means going from a deeper to lighter stage of sleep. So you may still be asleep throughout the night, but you're not getting deep slow wave sleep, REN sleep as much as you would uh otherwise. Do you create a buffer between your last bite of food and the time you go to sleep? You personally? Me personally, yes. Is it an hour, two hours, three hours? I personally like to eat my last meal at least three hours before going to bed. And I know there's variability there. Different people have different uh tolerance. You mentioned right before that uh you know some people may be later chronotypes, but what we know is that eating earlier is better overall for cardio metabolic health. Eating earlier is better. Me personally, I feel I feel better by eating earlier. If I eat too close to bedtime, I I get hot. Right. Yeah. It's it's a thermic effective food thermic effective. We want to be cooling off when we go to sleep. Exactly. Exactly. I'd like to take a quick break and acknowledge our sponsor, AG1. 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For a limited time, AG1 is giving away a free bottle of their new Omega-3 co-enzyme Q10 product. Omega-3 and co-enzyme Q10 are known to support cardiovascular health, cellular health and energy, generally, brain health, and much more. I personally take them both every day. Again, go to drinkag1.com/huberman to get a free bottle of the new Omega-3 co-enzyme Q10 with your first AG1 subscription. There seems to be something asymmetric about sleep requirements in my experience, and I don't think I'm alone in this, whereby if I go to bed at 1000 p.m., I get into bed at 9:30, fall asleep at 10:00, I need about 6 and 1 half, maybe 7 hours to feel completely rested. That's how long I'll sleep. Wake up without an alarm, feeling great. If I go to bed at midnight, I find I could sleep till 9 and still not feel completely rested. So, there's some weird sleep inertia stuff going on there, etc. The old adage is every hour before midnight is worth two after. But is there any real data to support that or is this just all subjective and conjecture? I'm not sure there's data to support that. I haven't seen anything. But what I can say from what you're saying is that if you usually go to bed at 9:30, 10:00, and then all of a sudden you go to bed at midnight, now you're kind of out of line with your personal circadian system, right? And it's always harder to to get a good night's sleep if you're not going with your internal clock or your internal circadian preference. Um, this is what happens with shift workers, right? for example, they they they're not sleeping at night. They're trying to sleep during the day. They're trying to sleep during the day where their melatonin is low or it should be when it's high. So, they're fighting their circadian system. So, yes, they should they should be getting seven hours, but they're not getting seven hours because their body is not designed to be sleeping during the daytime hours. Plus, then you have, you know, everything else, right? Right. The light, the lights, the noise, the kids, the whatever life that that happens during the daytime when everybody else is awake and you're trying to sleep. Yeah. The only thing I can think of that's an advantage to being nocturnal is the quiet. I used to sometimes shift to a nocturnal schedule during holidays in graduate school when everyone would go home because I lived my my parents lived relatively close to where I went to graduate school. So, I could afford to just just go home for Christmas, right? Just that day or a couple of days. and everyone else had to travel, so I could invert my schedule. It just kind of drifted that way. I promise that's the only advantage of going to bed at 4:00 a.m. and uh sleeping until, you know, 3:00 p.m. At least for typical people, it you your brain gets into a kind of weird space when you're inverted from the rest of the world. Well, the things you do when you're a grad student, I would be the opposite, right? I'd wake up at 4:00 a.m. and then study because I felt like all of the hours of studying before the sun rose were like extras. Interesting. Extra time for me. It was definitely extra. But you felt like you were extra sharp at those hours. Extra sharp. I could study and then you know I got that time done and then you know breakfast but then I crash later in the afternoon. Yeah, that's the problem. The one 2 PM crash. Um has your work explored napping at all? I'm a believer in naps and non-sleep deep breaths, yoga nidra type things, meditation. Do naps factor into this diet, nutrition, hunger equation. So, we haven't done research on napping per se. For me, there there's a lot going on with napping. I don't think we have very good data to be able to say what's appropriate about napping. What we do know is that you don't want to nap too close to bedtime because you want to build sleep pressure throughout the day. And if you're dissipating the sleep pressure, the sleep need too close to bedtime, then you're not going to be able to fall asleep when time comes to go to bed at your usual hour. And then, you know, you get into this vicious cycle and it's it's not helpful. But, you know, there are some studies that say, well, what should you do if you can't sleep enough at night? and you're feeling tired, you know, should you sleep? Should recommendations are that you should make it a short nap, 30 minutes, no more than an hour, early enough in the day if possible, so that you can have sufficient time to rebuild that sleep pressure to be able to fall back asleep well when time comes. But then there's also this this whole question about what's an app for, right? Like why are you sleepy? Of course, if you if you've pulled an alada, it's easy to to know. But if if you had sufficient sleep or sufficient opportunity for sleep at night and you're waking up and you're not feeling refreshed, you're not feeling like you had good quality sleep and then you're not able to maintain alertness throughout the day and you need a nap. I think it's you should check to see like what's going on at night like why are you not getting that good good enough sleep? I'm chuckling because my posttock advisor sparked this huge debate. It was a big lab and uh we had a couple of people in lab who like to nap at their desk. These were people that could just like put their head down and nap at their desk in the afternoon. He'd walk in, they'd be napping and then they wake up and keep working. Everyone everyone was working very hard. and he had this theory uh that if you're napping it's because you're sleepd deprived that like napping is unhealthy you know and it it sparked a big debate and people because it we're a bunch of nerds people bring data in like no you know at the sleep lab at Stanford says that naps can be healthy and I think it what you just described summarizes I think that the takeaway I'm a believer in the short nap but but I'm one of these people that can sleep anywhere anytime which may be reflective of sleep deprivation maybe yeah do Do you find that like when you're going to design a study or when you're going to like really work like this 4:00 a.m. time that it's a time of calm or are you like a laz are you do you feel like your mind is moving fast or you're kind of in this like flow zone or whatever you want to call it? I'm very focused. Uh very efficient. So I try to be really attentive at my task. I try to take take breaks once in a while, but uh most of the time it's uh it's very efficient. Get to the task and get it done. Earlier you were talking about biking into work. You strike me as somebody I always think of people who I'm always impressed by colleagues like this that their life is kind of like a step function. They wake up and it's like they're into the day and then it's down, right? Yeah. Interesting. I think some of us are more like this. But I think it's important to have a little bit of both though. I think it's important to have downtime, you know, speed time, uh to to not just be go go go go go like you were asking about uh my personal, you know, uh actions and at one point I was running a lot for exercise and uh I felt like my whole life was just running all the time. Yeah. Yeah. Run to get my kids to school. run to work, get work done, run to then run for fun. Run, run, run. And then I thought, okay, I kind of need to I think I need a breather. And so I started incorporating yoga into my uh my exercise routine. I think that's I think that's good. Actually, when I was a grad student, I thought yoga was stressful because I couldn't stand in those poses. Exactly. Yeah. Yeah. But I think yoga evolved. I think the yoga I do now, it's not as static as the yoga I was doing when I was a grad student. I think it evolved to be a little more active than uh than back then. I see the benefit to having, you know, the both types of uh exercise. Thanks for being willing to explore that. you know the I'm not an Ayurvedic practitioner but the Ayurvedic folks they'll talk about people like more fire more more earth where you know and and I think it's just a different lens in nomenclature on there's a kind of array of phenotypes but when we talk about this thing sleep it becomes very prescriptive right it's like we all need 6 to 8 hours I mean actually from what you're saying today six sounds like insufficient is what I'm hearing I'm probably a little sleepd deprived is what I'm kind of hearing so you know a colleague of mine just published a paper in nature about the biological clocks and aging in different organs. And the sweet spot really was 6 and 1 half to about 7 and 1 half 8 hours for optimal aging. Once you get to below that, it's basically you shaped, right? So too much of one thing is not good. Too too little is is not good. You want to be in the sweet spot. Most most organs for optimal aging was in the 6 and 1 half to 7.8. And it differed a little bit by men and women depending on which organs he was looking at. Uh a little longer for women. Um some of the curves were different where you know some are more pronounced u shapes in in men than women and different organs. So uh very interesting paper came out last week or two weeks ago. I'll have to check it out. Um what other uh sex differences uh are known to exist in sleep requirements, sleep dynamics that from your work or from other work? This is not something we've really covered on the podcast. No. No. I mean, well, not in in any sufficient amount of detail. So, women tend to sleep a little longer than men across lifespan. Although, you know, if you ask women about their sleep, they don't rate their sleep as very good. Um, more women than men report having difficulties with sleep. Insomnia for example, insomnia symptoms. More women than men say they have difficulty falling asleep, difficulty maintaining sleep uh across the adult lifespan. Why do you think that is? There could be some physiological effects, right? Some hormonal effects. Women uh don't sleep the same across a menstrual cycle. Uh there's discomfort at different times. Uh and then there's different responsibilities, different social roles that come into play uh that may influence women differently than men. But you know, we were working on a on a review paper actually about hypertension and and sleep and sex differences. And you know, women are more sensitive to the impact of poor sleep on different metabolic outcomes than men. So for blood pressure at lower sleep apnea for example at lower thresholds of sleep apnnea their blood pressure would be higher uh than men. So I think that there needs to be for sure a lot more research in this area to be able to uncover you know these these differences and then you know knowing that there are these differences to start probing uh women about their sleep. Last year we published um a scientific statement for the American Heart Association about multi-dimensional sleep health and we concluded by uh recommending clinicians that they actually ask their patients about sleep and not ask a question a targeted question just ask their patients how's your sleep because if you start asking about oh how much sleep do you usually get at night then you tell the person that the only thing that matters is how many hours of sleep you got at night That's not all sleep is about, right? Sleep is not just about the number of hours that you got, but it's also about the regularity, the quality, your satisfaction with it. Your there's nighttime experiences, there's daytime experiences from sleep. When you wake up from sleep, are you feeling refreshed? Are you feeling like you had are you satisfied with how the sleep you got the night before? During the day, are you staying alert? are you vigilant during the daytime hours uh from your past sleep experience? So having this open-ended question maybe maybe clinicians uh won't have time for for a for the answer but you know allows the their patient to actually tell them what's bothering them about their sleep. Then you can get something like you know my my spouse keeps kicking me because I'm snoring too loud. Then oh well maybe we should test you for sleep apnnea. Does apnea always include snoring? So, are there some people who don't snore who have apnea? I don't think so. You stop breathing and then there's this gasping sound that people make when they uh they awaken from that or they get aroused from from this breathing interruption. I feel like so many people have apnea and don't realize it. Not because I'm sneaking into their rooms at night and listening to if they snore, but it is just remarkable how many people I speak to who say, "Yeah, I found out I had apnea because I saw that I was snoring because they started monitoring their sleep." And there's generally a snoring index on these. Or now there are free apps that can just record you while you So, I know a lot of people are I don't mouth tape when I sleep, but I did I do uh sometimes use one of these nose strips that kind of pulls the nostrils out a bit. That certainly it's reduced the amount of snoring for me that would reduce the amount of snoring but the sleep apnea is from the throat right so this closure in the throat that that obstructs the trachea and that's what then prompts the awakening and breathing and then the sound that comes from there actually weight loss is typically like the first line treatment if someone has excess weight to start losing weight that might help with the uh with sleep apnnea then there's sepat which yes people don't like but if they are at a lower weight where the apnea is milder the pressure may be not as uh not as high so that might be helpful for comfort have a colleague of mine who does uh sleep apnnea surgeries so implantables are also if people think they might have apnea is it just get a cap pop that thing on is that the best line of of entry I I think they should uh they should get tested. How do we how does one do that? Cuz that's the problem. If you're suspecting that you may have sleep apnnea because you've been told that you snore because you wake up and you're not feeling refreshed and you're feeling sleepy during the day. I think you should talk to your doctor about this. And definitely we have polyenography is the first line, you know, is what we use to detect um sleep apnnea. But there's inhome sleep testing that can be done. So you don't have to stay overnight in a lab for for uh to get tested for this and uh and your doctor can prescribe that test very easily. How come we can't just go buy a CPAP on Amazon? Because you need to have the the the pressure determined for you, right? So you need to know what kind of pressure to apply and you know how to set it up. Uh it's not as as simple as just All right, fair. You need it. It needs to have the proper settings and someone needs to tell you which setting to use because then that's where you run into the trouble of having the wrong settings and and not being effective. Yeah. I just know from having done this podcast long a while that like if people think, okay, I got to go to my doctor. I got to find out or convince them that I have apnea. Then they have to like write me a script for a CPAP. Then I got to buy a CPAP, which I'm guessing is not cheap. I'm not sure. I I don't think they're very inexpensive. They the price might have come down. and I got to sleep with this thing on my face like looking like Darth Vader so I don't sound like Darth Vader. I just think very few people are going to do it. So somebody out there should like come up with an at home solution to this. Something like apnea seems important enough to daytime wakefulness, cognitive function, longevity, metabolic like it wicks out to so many things that I feel like it it deserves it deserves like a public health messaging. Yeah. If you use it well and you feel better during the day, that's a that's reinforcing, right? To keep using it and and get treated for it. Let's talk about food and nutrients. You've done a substantial amount of work here in this area, and I have a bunch of questions, but first I want to talk about kefir. I love Bulgarian full fat plain yogurt, but it's right next to the kefir. Uhhuh. And I'm always like, do I get the kefir? Well, I don't know. I love the Bulgarian full fat plain yogurt, so I haven't tried the kefir yet. What's special about kefir and why why did you study kefir? Kefir we we studied because it was a fermented dairy product uh probiotics we figured you know maybe it will improve uh cholesterol synthesis based on its impact on short- chain fatty acids. So that was the the subject of my master's thesis for that study uh that was when I was at McGill. We recruited men that had mildly elevated cholesterol levels. We gave them two cups per day versus just regular milk for a month. So two cups like two mugs like this. Two cups like the measuring cup. Okay. Um like 500 mls. And uh and we measured their the amount of cholesterol they they produced at baseline endpoint in both phases and there was no effect. It was a null study. It was one of those. It was hard to get published. Kept at it and and we got it published. But yeah, so these fermented yogurts and things, they don't do anything for for cholesterol levels. At least in our study in this population at this level with this comparison didn't have any effect. What's your general thought about uh low sugar fermented foods? I don't know if kefir uh qualifies as low sugar, but based on Justin Sonnenberg's work at Stanford and others, I've been I've been really bullish on this idea of sauerkraut, kimchi, uh full fat Bulgarian yogurt. Fermented foods are are interesting. Are you a proponent in general? I'm a proponent. Yeah, absolutely. I think it's important to feed your gut. I think that uh the gut microbiome is uh getting a lot of attention for all sorts of, you know, uh health benefits. So I think that that's something that's uh that's is important. So also it's important to also consider that you know for that study right our main outcome was cholesterol synthesis but there's so many other things we could have looked at that we didn't look at right and maybe it didn't have any impact for cholesterol synthesis but maybe glycemic control might be better or for gut inflammation it would be better but you know You pick your outcomes, right? You study something. This is the challenge of doing controlled science. Yeah. Yeah. Sort of the opposite end of the like X what used to be called Twitter science where like people just like report anecdotes but actually anecdotes of that sort of become very powerful now in the public health space for better or worse like people you know because I we can look at any study and say well that's a very artificial circumstance. You say, "Well, intentionally, because we're trying to isolate variables like people get frustrated." Oh, that's an observational study. Well, I'm going to continue to eat low sugar fermented foods every day. I I I do think in a study like the one you described. Occasionally, there's just there's, let me state this differently. Historically in science, there have been a lot of interesting discoveries that have come from researchers designing a study to look at one thing and then kind of noticing, oh, like all the subjects feel better or sleep better, their skin, they they're reporting things that then lead to another another line line of inquiry. But you moved on from kefir. Tell me about this um this paper. I was intrigued by this when I looked over your CV. uh a weight loss diet that includes a coffee beverage enriched in let me try this menolosaccharides. Okay. Long word leads to a greater loss of atapose fat tissue than placebo beverage in overweight men. Yep. Tell me about this study and what these men oligosaccharides are. And if somebody wants to lose weight, should they be including this in their coffee? So this was industry sponsored research that I did. um they wanted to replicate a study that had been done in a different country because they wanted to replicate the findings. So we did this study uh it was basically a placeboc controlled study. We got we were provided um coffee manual oligosaccharides. So these are extracted from spent coffee grounds. So it was basically satchets right? So a white packet one had the cap coffee manualsaccharides the other one didn't. We gave it to our study participants. We measured their body composition. We found an effect on body composition in men, not in women. And so that was the end of that product. Really? They wouldn't market it just because it only had an effect in men. I assure you there are many men who would love to drink a coffee drink and lose more weight as a consequence. It's not going to be our market, you know. But do we know what the ingredients were? It was manualsaccharides extracted. Yeah. So it was just uh basically uh a product that was tasted like coffee, strong coffee, but it didn't have the caffeine or anything like that. It just had this this manualaccharide that was extracted from coffee. So this substance comes from coffee ordinarily, but coffee is very low low calorie on it, but it's from the spent ground. So you no one really consumes this really because you know when you brew your coffee you're not getting it. No. Can you buy it? Can people get it? I don't think so. what what do you First of all, how much weight did they lose relative to the It was statistically significant. Yeah. Okay. I was intrigued by it because I thought there there's something that I mean you studied it's interesting. You studied kefir metolosaccharides from coffee. Yeah. Now I'm going to ask you about ginger. Well, when I was a graduate student, I was interested in functional foods. And I was interested in those foods that provide health benefits beyond their nutritional value. Right? So kefir is a fermented dairy product. It would we were studying it for its a functional benefit on cholesterol synthesis. That's not a uh that's not a function of dairy, right? Dairy is you consume it for bone health, right? So it's basically when we talk about different claims that foods have, you know, there's those structure function claims like consuming dairy contains calcium that's good for your bones and then there's um functional claims. Those functional claims or health claims we call them that say okay well health claim there's a health claim for oats for example, right? So consuming fiber from oats uh reduces cholesterol levels. That's been demonstrated. Yes. So that's that's a health claim. That's an approved health claim. That's why you see the hearts on some boxes of cereal, but that's different than fiber is good for maintaining regularity, right? So anyways, I was interested in in functional foods for health benefits beyond their their nutritional content. And so uh we we studied kefir for I studied kefir for my master's degree and then for my PhD studied uh mediumchain triglycerides um and then um ginger that was uh that was something that I that I uh offered to a grad student at Colombia. It was interesting because uh the McCormick company had an advertisement in uh one of the nutrition journals and they were going to donate um spices for research. I was like, "Okay." They had a list of different herbs and spices that they were going to donate for research. And I had a grad student and I said, "Take a look at this list, come back to me, say if there's something in there that we should test in the lab based on the things that I do, don't come to me with something that's, you know, that I don't study." But and then he did some research and he came back and he said, "I think we should study ginger." I'm like, "Okay, to do what?" like I think you know for energy expenditure looking at thermic effect of food it's like okay so so we did this study I had some some funds that I could use for him to do that and uh what did the study look like a study where we looked at the thermic effect of food like so people ate ginger root spicing their food we dissolved ginger powder in warm water and so that was one beverage and then uh in the crossover again crossover design so the next time when they came it It was just hot water. And how many times a day are they drinking it? This was a one time one time uh consumption period. And we looked at the thermic effect of food over a 6-hour period. So again, they're they're under this um we call it a metabolic hood, right? So a little bubble and we measure their uh oxygen consumption, carbon dioxide production for I think it was four or five hours and it's significantly elevated. With ginger. Wow. So we think through the capsain receptor there's an increase in the thermic effect of food. So yeah, so I was interested to see are there little things that we could do, little changes we can make to our diet to boost energy expenditure relative to intake, you know, just to tip the scale because many adults over the course of their life lifetime gain weight. And it's not a big imbalance in calories on a daily basis that leads to 10 pounds of weight gain over 10, 15 years, right? Now again the GLPs are coming in and adjusting but yeah I'm very interested also in foods that have impact beyond their you know known known roles. I mean the the problem is in this area in the functional foods area not the problems with your work but the is that there are a lot of wild claims that go unchecked like oh you know walnuts are shaped like a brain and therefore they're good for your brain or you know which is they have certain things in them which are brain beneficial but it's not related to the shape of the food so you get there's a that area I feel of nutrition has been um marginalized on the basis of the kind of like quackery associ with it. But of course there are interesting things in different foods. I I do think that the the Sonnenberg and colleagues work on low sugar fermented foods has been very informative for lowering the inflammatome even more than fiber. I mean actually in that study this is kind of the like even Justin will kind of downplay this a little bit. He's a colleague so I can say in the fiber group when they compared to low sugar fermented foods and then they measured the inflammatome they did a crossover design. Within the fiber group, there was a fair number of people who their inflammation went way way up when they consumed more fiber. But in the low sugar fermented group or when they were in that group, it was it was uh always on average reduced. Some people who increase their fiber intake, their inflamm decreases. For a lot of people, it increases, which is not to say that fiber is bad, but I think now we're starting to think about like different types of fibers. I was going to ask. Yeah, they didn't control for that. They just said increase the number of servings each day. And and I know a lot of people don't like to eat fibrous foods because they don't feel good after they eat them. It's like it's not that they don't taste good. And I think there's this whole like histamine story that needs exploration. I I think food and the healthy foods needs better parsing. In in my opinion. Yeah. I I mean there was also habituation. You don't go from consuming six grams of fiber per day to 25. They ramped them up. But but I have to say they ramped them up pretty high. Like even the low sugar fermented foods, I think they got them up to like four servings per day. It's a lot of kimchi. You're not familiar with it. Like it can be a little hard on the gut. I actually take an enzyme. I think it's called DAO. Very inexpensive little it's like a tiny tiny pill that uh that for digesting histamines because I noticed after I had whey protein or I had broccoli or I would I would get kind of sleepy. I was like what is this? and a a a colleague at Stanford, Sean Mackey, who's our head of our pain center, said that he had gut pain at one point, he's a pain doctor, directs the pain center, and he figured out by elimination and trial and error that it was onions and other histamine containing foods. He avoids histamine containing foods. I'm not about to give up the things I just described. Onions I can do without, but so I think that there's a there is foods have real effect. M. So kefir, these men olosaccharides, I have to confess I'm a little disappointed cuz like here it looks like it has like a cool effect, but they didn't they didn't want now can't get them. I'm not going to eat coffee grounds. I'd like to take a quick break and acknowledge our sponsor, Helix Sleep. Helix Sleep makes mattresses and pillows that are customized to your unique sleep needs. Now, I've spoken many times before on this and on other podcasts about the fact that getting a great night's sleep is the foundation of mental health, physical health, and performance. When we aren't getting great sleep on a consistent basis, everything suffers. And when we are sleeping well and enough, our mental health, physical health, and performance in all endeavors improve marketkedly. 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Helix has also teamed up with TrueMed, which allows you to use your HSA FSA dollars to shop Helix's award-winning mattresses. Again, that's helixleep.com/huberman to get up to 27% off in your work or in your observation or in your curiosity. What other foods are kind of intriguing to you? Someone had a really um great question for me at the obesity society meeting a couple of years ago. I was showing data that we had just obtained in the lab that showed that if you eat foods later in the day, your fat oxidation is reduced. So this is a study that we're doing. We had uh participants on a controlled diet and they started eating 1 hour after waking up and they had a 10-hour eating window or they started eating 5 hours after waking up. So 4-hour delay relative to the other condition. Again, same thing for a 10-hour window, 10-hour window. We gave our participants the exact same foods, same foods, same quantity, same timing between meals. And this was done in a metabolic chamber. And the meals, especially the meals later in the day that were consumed late relative to the earlier version of those meals led to less fat oxidation. and someone in the audience stood up and said, "So, would you then recommend that people eat mediumchain triglycerides in their evening meal as opposed to, you know, a a different type of of fat?" And my eyes just went like this because, you know, my the my time studying medium chain triglycerides was, you know, 15 to 20 years ago. I was like, "Wow, this person knows my that work that I've done and now is applying it to this work that I'm doing currently." And I thought that was fascinating. And I think that, you know, timing of intake of different foods and how it influences metabolism is something that's uh that's fascinating to me. I confess I'm a like first bite of food around 11:00 a.m. person. I'm trying to eat breakfast these days and then kind of shift things earlier. All it's really done is added a meal because I I take my last bite of food usually around 8:00 PM. I just can't seem to get much earlier. But I and many other people have wondered whether it's best to eat more towards early day or whether or not it's just overall caloric load. You're saying that it does indeed make a difference. It makes a difference. Yeah. You want to shift most of your caloric intake to the first like twothirds of your waking day roughly. Mhm. Yeah. As opposed to the last 2/3. Yes. Yeah. So, in that study, 1 hour after waking up. So, let's say basically 8:00 a.m. to 6 p.m. is our eating window. I mean, this is a 10-hour eating window. It's short. It's not, you know, typical. So, it could be 8:00 a.m. to 7:00 p.m. That seems pretty That's reasonable. Yeah. Versus 12:00 p.m. to 10:00 p.m. The New York schedule. Yeah. The New York schedule. Yeah. Well, I I sort of chuckle because when I go to New York, like it's like if you go to dinner at 5:36, you're kind of alone in the restaurant. Depends on time of year. Early bird special. Yeah, it depends on time of year. And in California, it's it's kind of in it's the early shifted. But that's just more reflective of culture. I think in Europe they they eat very late often. Depends on where. I I I was saying before we we started I was on a fullbrite uh program last year in in Spain and uh I would joke with my with my colleagues there because they eat very late and even the children eat very late and I was like okay well you feed me then you feed the children right then you have your dinner because they could have dinner at 10 11 p.m. and the children 8 900 p.m. And I'm like, can't be good. If you uh my dad's from Argentina, if you go to a restaurant in Buenos Cyrus at 9:00 p.m., you're not going to see many people at 11:00 p.m. You'll see people in their 70s and 80s and they're up early the next day. They nap in the afternoon. I don't know how healthy they are as a country on average, but haven't looked at the data, but very very late shifted culture. Well, there's been studies in Spain that have looked at timing of eating and their impact on weight management. I'm thinking of work by Marta Garullet where she showed that in her um weight loss program the participants who have lunch so their big bigger meal is is lunch who have their lunch earlier in the day have better weight loss than those who have their lunch later in the day. So you know even in those cultures where they have they tend to eat late they still find that eating earlier is tends to be better for you. I was very very relieved when um Alan Aragon who's a I consider one of the best public educators on the topic of protein and nutrition body recomposition he's formerly trained in this reassured me that you know nowadays there's a lot of interest in getting like protein ration it's probably overdone a little bit but people are striving to get more high quality protein but that except in rare circumstances where people are really trying to optimize every bit of muscle protein synthesis 95% of the effect of getting enough protein can be accomplished by having like two meals. Maybe a little snack that you don't and it can be evenly distributed or unevenly distributed. You know, I think a lot of people are feeling this protein pressure and like, oh, I got to eat another meal late in the day or I have to force myself to eat breakfast in order to get their protein ration. But it turns out the whole notion that you could only assimilate like 30 grams per meal is totally false. turns out can assimilate up to 100 gram. Now there are conditions that set that up like exercise etc. But I find that very liberating like you could have breakfast and an early dinner with a snack in the middle. You could miss breakfast, have lunch and an early dinner. What I'm hearing from you, however, is that you really want to avoid the the big even or just late dinner. You just don't want to eat too close to bedtime. Correct. What about these MCTs, medium chain triglycerides? These were very popular in the health and kind of biohacking space a few years ago. The um the whole bulletproof coffee notion, MCTs, butter coffee, and that's more or less faded away. I don't see a lot of people putting oil in their coffee these days or coconut. What are some of the known benefits of MCTs? Where do you find them and what what brought you to them as a research topic? This was a topic for my uh PhD dissertation. So my PI got a grant looking at the medium chain triglycerides. He had done prior work on this. Uh but what we did was use purified MCT oil. So this is only uh liquid oil that contains 8 carbon and 10 carbon chain fatty acids. Those are not very common in our general food source. So it was purified extracted oil that we then gave our participants. We had created this functional oil um that contained flax seed oil also to be able to get some more some omega-3 fatty acids in there. Uh we had added plant steriles because that was a big um big focus of my lab uh at McGill. Plant steriles for cholesterol reduction and uh reduced uh risk of cardiovascular disease. And uh but the idea was to evaluate the impact on energy expenditure because the way we process mediumchain triglycerides is different than how we process longchain triglycerides. So the 12 14 16 and up uh carbon chains. So the medium chain triglycerides they travel directly to the liver they get metabolized. we burn them off more readily than the longchain triglycerides that travel across in peripheral circulation get deposited in atapost tissue and a sort. And so what we did what we found we did two separate studies in men and women in both men and women there was an increase in thermic effect of food. So you burned slightly more calories from the meal that contained medium chain triglycerides compared to the meal that contained your standard fat. for my PhD. The first study we did, we did in women and we were trying to match the saturated fat content of the diets because uh mediumchain fatty acids are by default saturated. They're 80 10. So I said, okay, we're going to try to compare that to a uh a saturated fat matched control comparison. And we used beef tallow. Uh it was a lot of beef tallow. Uh participants were not happy with that diet. Eat it. Eat it direct like spoonfuls of beef. We put it on to mashed potatoes. You know, when you're when you're doing studies like this where you're trying to control the diet and you want to isolate one aspect of it, right? We gave real foods. half of the total fat of the diet came from the the medium chain containing versus and the beef tallow. So it's like 20% of your fat from one of the two. So you have to pour it mask it somehow and MCT. There's also this issue about laxative effect of MCT oil that that we had a few participants who initially felt a lot of gargling when like just gargling from their stomach uh from from consuming MCT cuz it was a lot early on it resolved. So after a few days it was fine. It was a one week one month I mean four week study. So after a few days no one dropped out for you know any GI issues. Okay. That's reassuring. Yeah. So, beef tallow it was initially uh beef tallow because it has a lot of saturated fat is solid at room temperature. So, as soon as your food started to get a little colder, it would kind of gel on your plate. Yeah. That's sort of like if you bring French fries home from a restaurant, they use tallow and then you like put in the fridge cuz you thought you wanted them as leftovers and the next day they're sort of like in this like stuck to bottom of container configuration. Yeah. It's not very appetizing. Not appealing. No, there's like it's white all underneath. Yeah. It almost always goes into the trash. A couple of women felt it gave them a headache. Just the smell of it, you know. So with the MCTs big significant increase in thermic effect of food that was statistically signing. Yeah. It was about 45 to 50 60 calories. Oh, I thought you were going to say percent increase. Oh, no. So, it's it's a small change, but it was if you're going to use this versus that, you're getting a little boost here. If you repeat this a few times in a day, because when we measured the thermic effect of food, we measured it only after over one meal, but repeated over three meals per day over a certain period of time. We did find changes in body composition, improvements in um in weight status with medium chain triglyceride consumption, lean mass to to fat mass. Interesting. And then we did follow-up study of a weight loss study with medium chain triglyceride. This time around it was just purified MCT oil, not added with other types versus olive oil, uh, which is much more acceptable and found greater weight loss with MCT. Based on what you're saying, it's reasonable if somebody wants to improve weight loss. I'm hearing a sort of a constellation of things. shift your meal timing to in the first twothirds or so of your day, which sounds like it will also improve sleep, which will also improve uh appetite and food regul satiety and hunger signals. What is it like a tablespoon or two of MCT per day? Is that kind of what this looks like for the typical person? Yeah, about that. In place of some other oil, not in addition. Not in addition. Correct. Okay. Some ginger. Are they additive? Are they synergistic? I think they could probably be additive because I think that the impact is through different mechanisms. Obviously, no one's tested that. Um, you know, it's interesting you bring it up this way because it makes me think of um David Jenkins and the portfolio diet. It actually made the New York Times uh I think last in December. The portfolio diet uh was a diet he designed for maximal cholesterol reduction. So, it was initially designed to have uh four specific foods. So, it was high in soy protein, nuts, plant steriles, and soluble fiber. Yeah, it's going to be a tough one to get past most of the American public. I'll tell you, as a as a public health educator, I don't care if it comes out in the New York Times, the Wall Street Journal, the New Yorker, and everything in between. People hear soy. Nuts they like but easy to overeat. Mhm. They hear plant steroids and like they're they're they're someplace else. This diet was went on a head-to-head comparison with lipid lowering agent, right? Like a statin. Yeah. Yeah. They had the same uh cholesterol reduction as a statin. As a statin. Yeah. The portfolio. Interesting name. People are definitely unhealthy in this country. And if if they can lower blood lipids Yeah. They've expanded it to u to be more flexible. So it's not just soy protein now. It also includes legumes. They've added monounsaturated fats. So olive oil. You know, when I look at a diet like the portfolio diet, which you just I only know what you just told me about it. Or I think about the the current food uh uh suggestions by by the FDA which are you know we could call it kind of um it emphasizes um unprocessed and minim minimally processed food. So I think that's a step in the right direction. Certainly, we look at these. The issue that always comes up for me is I think, okay, in a more plant-based um grainheavy nut diet, it's very easy for people to overeat calories based on this whole like amino acid protein foraging hypothesis. This idea that we eat until we get enough of the amino acids we want. Like a like a an a chicken breast or something and a couple eggs or or or four eggs or something is very satiating. M whereas we can eat a lot of grains and nuts before we kind of go okay that's enough. There seems to be this issue like how do how do you ensure cardometabolic health while quelling hunger and we can't have people walking around hungry all the time and the GLP's help with that and it does get down to sort of like do you include animal-based foods or not often. So how do you think just from a public health perspective that we can reconcile this because clearly the highly processed food diet is not going to work. the standard American diet that I think that is fading away. But now there's this kind of polarization of like are we going to go mostly plants, grains, nuts, and I think low saturated fat, blood lipids improving, or are we going to think like, you know, more protein satiety? Do you see where I'm getting at here?…

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