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There is a very, very small, tiny change that I'd like you to consider making to your daily routine. And from where I'm sitting, it might just be one of the highest return shifts that you could ever make for your long-term health.
Learn why avoiding late-night eating can dramatically improve your health by aligning with your body's circadian rhythm.
Ask about this video. Answers come from its transcript only — with the timestamp, so you can check them.
Generated from the transcript and can be wrong — check the timestamp.
Key Takeaways
- Avoid eating close to bedtime to support your body's natural repair processes.
- Late-night meals disrupt blood sugar, blood pressure, and hormone balance, increasing disease risk.
- Chrononutrition is a critical but often overlooked factor in overall health.
- Small timing changes in eating can lead to major health improvements over time.
- Consistent practice of this habit can reduce reliance on medications and improve sleep and energy.
What the video covers
- A small change in when you eat, specifically avoiding food close to bedtime, can significantly improve long-term health.
- Nearly every organ in the body has its own circadian rhythm, which governs digestion during the day and repair at night.
- Eating late at night disrupts these rhythms by signaling organs to stay active when they should be resting and repairing.
- Late-night eating impairs blood sugar control, increasing risk for insulin resistance and type 2 diabetes.
- It also blunts the normal overnight dip in blood pressure, raising cardiovascular risk.
- Hormonal imbalances occur with late eating, including elevated cortisol and reduced melatonin effectiveness.
- These combined effects contribute to chronic diseases similar to those caused by stress, poor sleep, and unhealthy diets.
- The speaker shares a personal health turnaround, including stopping strong medication for acid reflux by changing eating times.
- Research by Professor Satchin Panda and others highlights the importance of chrononutrition—the timing of food intake.
- Implementing a daily fasting window by not eating late at night is a cost-free, high-impact habit for better health.
Chapters
- 00:00Introduction to a small but impactful health habit
- 01:19Personal health transformation and medication reduction
- 02:56Understanding circadian rhythms in organs
- 04:23Chrononutrition and timing of food intake
- 05:47Effects of late-night eating on blood sugar and blood pressure
- 07:27Hormonal impacts of eating late and disease risks
- 08:47Personal experience with acid reflux and medication
- 11:38Benefits of fasting and long-term health improvements
- 14:51Summary and encouragement to adopt the habit
Full Transcript — Download SRT & Markdown
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Now, I'm very careful to say one of rather than the single biggest because obviously I talk about diet and exercise and, you know, other daily habits all the time across this channel. But this particular shift is one that I haven't
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really mentioned before, and it sits alongside all of those other habits I talk about all the time, and very few people that I actually meet are actually doing this. But the thing is, because this change is so tiny, I want to
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introduce it a bit carefully in this video because I bet a lot of you would immediately hear it and decide it's either too obvious or too simple or not significant enough. So bear with me in this video because I want to take you
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through what the research has uncovered over the last decade or so, share with you what's changed in my own health when I made this shift, and then explain how to do it yourself. The habit itself is really straightforward, but the reasons
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it works are far more interesting. Now, I'm going to be completely honest and say that I've been doing this for quite a while now. And the difference it's made to me personally has been one of the biggest turnarounds I've ever had
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with my own health. And I say that because a medical condition that I've got that I've been on strong medication for every single day for years, it gradually eased to the point where I no longer needed that medication at all
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because of this habit. My sleep improved. My energy through the day improved. And the curious thing about all of this is that nothing dramatic actually changed about what I ate. The change was purely in when I ate, specifically not eating close to
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bedtime. And there's some very specific physiological reasons why that is so important. Now, to understand why this works, you have to understand that nearly every single organ in your body runs on its own internal 24-hour clock.
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And these clocks together are called your circadian rhythm. Remember, it's not only your brain that knows whether it's day or night. Your liver and your gut and your pancreas, your heart, even the muscles in your arms and legs, each
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have their own circadian rhythm, switching on certain genes and switching off other genes depending on the time of day. So during the daylight hours, when you're meant to be active, these organs are tuned in to take on fuel and digest
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it and to put it to work. After dark, after you go to bed, they shift their mode entirely. They wind down digestion and they turn instead towards repair and restoration and cleaning waste from your cells. Every single part of your body
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does different things in the nighttime compared to when you're awake. And this division of labor is a deeply evolved survival advantage because no organ can perform two opposite jobs at once. So doing the work of digestion by day and
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then the work of repair at night has kept us very efficient and healthy for tens of thousands of years. The single most important point to grasp is this.
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So light is what synchronizes the master clock for your brain. But for most of your other organs, the strongest signal isn't light at all. It's food. The moment you eat something, your first meal of the day, your liver and your gut
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conclude that it must be daytime, and they switch back into their active digesting state. So, when you eat a meal at 10 or 11 or 12 at night, or you get a kebab on the way home after a night out,
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you are sending a signal to all of your organs that says, "Wake up. It's daytime," you know, during a time when they should be repairing and restoring themselves. A lot of what we now understand about this process comes from
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the work of Satchin Panda, who's a professor at the Salk Institute in California. So, he spent the last 15 or 20 years or so leading some of the most influential research in this entire field. Professor Panda's lab essentially
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pioneered the modern-day study of what we now call chrononutrition, which is the science of how the timing of food, not just its content, actually shapes our health. When you eat close to bedtime, there are several different things that
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happen all at once, that very quietly raise your risk of lots of different kinds of diseases. The first one is that your blood sugar control completely falls apart at night. Your pancreas and your muscles handle a meal far less well
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in the evening than they do in the morning, even if the meal is identical.
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The same plate of food eaten at 9:00 in the evening will spike your blood sugar much higher and keep it elevated longer overnight than it would do if you ate that same meal at 9 in the morning because the cells that are supposed to
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mop up that sugar are quite literally winding down for sleep. So if you repeated that night after night, year after year, decade after decade, then you very slowly nudge yourself towards insulin resistance and type 2 diabetes, which is literally one of the biggest
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drivers of heart attacks and strokes that we know of. The second thing is what happens to your blood pressure. So your blood pressure is supposed to dip overnight by around 10 or 20%. It's quite a big drop, which I've covered in detail
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in lots of different other videos. So that dip is part of how your cardiovascular system rests and recovers. When you eat a substantial meal close to your bedtime, you redirect a huge volume of blood to the gut to
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handle that digestion. You raise your heart rate and you blunt that nocturnal dip. Over the long term, that blunted dipping, or, you know, where your blood pressure doesn't go as low as it should, is independently linked to a higher risk
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of heart attack and stroke and heart failure. Now the third one is the impact of the hormones that should be settling down at night. Cortisol, which is your main stress hormone, is supposed to be at its lowest as you fall asleep. But if
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you eat late into the evening, particularly anything sugary or refined, which is what most of us eat these days, that drives a cortisol response on top of an insulin response, keeping your body in a very low-level alert state
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right when it should be trying to calm down and get ready for sleep. And melatonin, which is literally the hormone that prepares you for sleep, doesn't pair well with insulin. When food and melatonin compete together at the same time, the body handles glucose
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much less well, which is part of why nighttime meals seem to land particularly badly. So if you stack those three things together, so blood sugar, blood pressure, and then also the hormonal problem as well, then you start to see why late-night eating is now
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treated as a genuine risk factor for all these different chronic diseases in its own right. What's really interesting though is that we already know plenty of other habits that cause this exact same trio of problems. Things like chronic
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stress or poor sleep or smoking and a diet full of ultra-processed foods. And most people would readily accept that those are bad for the heart and your brain and everything else. But very few people seem to realize that eating late
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at night produces almost the same internal pattern in your body. The damage is the same shape. It's just arriving through a different door, which is why your body is so complex. There are lots of different things that you do
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all day every day that can cause big problems in your health. I want to tell you about my own experience with this app because it completely shifted how seriously I take this. So, as I've mentioned before, for a long, long time,
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for many, many years, I suffered from really, really bad acid reflux. I would get horrendous pain in the center of my chest, spreading across both sides, into the back, in my throat as well. And it would make me feel sick on a daily
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basis. The only thing that I found would work was literally dissolving spoonfuls of bak
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medication. And I took it at 30 milligrams twice a day, which is pretty much the highest dose or one of the highest doses you can take. And I did a video specifically on this a few weeks ago about how I managed to come off this
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medication. Now, eventually I had an endoscopy or an OGD, a gastroscopy, which is where they pass a camera into your mouth through your esophagus into your stomach. And it turns out that I've got a condition called a hiatus hernia,
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which it isn't that uncommon to be honest. In simple terms, this is where the upper part of the stomach pushes through the diaphragm, which is that big sort of flat muscle that separates your chest from your abdomen just here, which
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weakens the valve at the top of the stomach that normally keeps acid where it belongs. So, I had or I still do have a genuine physical structural problem that causes this reflux. For me, it's not just a habit problem. But what
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changed everything for me wasn't this medication. It was stopping eating late at night. Once I started closing my eating window earlier on in the evening and giving my stomach plenty of time to empty before I lay down, the symptoms
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began to fade away. So I harved the dose. I was taking 30 milligs just once a day instead. And then I harved it again to 15 milligs just in the morning.
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And eventually I came off the lands of Brazole entirely. Now these days it almost never bothers me at all. And on the rare occasion it does I just take a couple of renies but that's probably twice a month if I'm being honest. Now
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the hernia obviously is still exactly where it was. It is still there. Nothing has been done to address the structural cause. But what that obviously says here is that this very simple lifestyle change, not having food in my stomach
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when I lay flat, because obviously when you're flat, stomach acid, which is produced to digest food, can then track back up into your esophagus because there's no gravity there to keep it down. This tiny change managed to reduce
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the symptoms of a structural problem inside my body more effectively than a powerful daily medication ever did. It really does bring home just how much our daily choices can shape what our body actually feels. And the thing is, if you
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eat late at night often enough, and if you get heartburn often enough, it's not just the heartburn that's just benign.
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You're damaging the lining of the esophagus over the years, which raises your long-term risk of conditions like Barrett's esophagus and esophageal cancer. So late eating isn't just uncomfortable for some people. It has serious downstream consequences. It also very quietly degrades your sleep. While
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you're digesting a heavy meal, your body is having to redirect blood to the gut and keep your heart rate slightly elevated to process all of that food when it should be deep in restorative sleep. Even if you fall asleep just
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fine, we know that the quality of your sleep is reduced because of the digestive work going on all at the same time and you will wake up less refreshed than you should be. So obviously the simplest way to fix all of this is to do
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all of your eating inside a defined window during the day and leave a proper long fast overnight. So, in our house, we normally do a 14 or 16-hour overnight fast as the default. We don't really think about this as fasting. It's just
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when we have our evening meal and then when we have our breakfast. What's happening inside you during that overnight window is really worth understanding properly, though. So, for the first several hours, your body works through the glucose left over from your
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last meal. It then begins drawing down on its glycogen stores, which is the form of carbohydrates stashed in your liver and your muscles for pretty quick access. And then once that glycogen runs low, which starts at around 12 hours,
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your body then shifts gear and starts breaking down fat for fuel instead, producing very small amounts of ketones in the process. So, even just a very brief gentle dip into ketosis once a day appears to bring pretty good benefits,
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including improved insulin sensitivity, lower inflammation levels, and the activation of the body's cellular cleaning systems where damaged components of the cells are recycled rather than left to accumulate. And obviously, this becomes a lot more powerful if the amount of carbs you eat
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during the day is as low as possible as well. And I did a whole video on the keto diet. I think it was around an hour and 20 minutes long a couple of weeks ago if you want to check that out. Now,
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there's a deeper benefit to all of this as well. It's what we call metabolic flexibility, which simply means your body's ability to switch easily between using carbohydrates and then fat as fuel. We can use both of them. A healthy
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body should be able to flip between the two without any fuss. And that flexibility is what our ancestors relied on for hundreds of thousands of years because food wasn't constantly available. And being able to coast along on stored fat through a very lean
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stretch was the difference literally between surviving and not surviving. Modern eating with snacks and meals running constantly from breakfast until bedtime never lets the body practice that switch. So, we lose the ability to burn fat efficiently. So, training
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yourself back into a daily fast, even if it's just 14 or 16 hours overnight, retrains exactly that machinery, the same machinery our biology was actually built around. And the clinical work surrounding all of this has now become pretty substantial. So in 2019, the Sulk
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team, the Sulk Institute ran a study on people with metabolic syndrome, which is this cluster of conditions that includes things like blood sugar and blood pressure and abnormal cholesterol and excess visceral fat as well. And they simply asked all of these people in this
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study to do all of their eating within a 10-hour window without changing what they ate at all. So, basically, they were eating for 10 hours and then fasting for 12 hours overnight, which is basically having your evening meal at
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6:00 p.m. and your breakfast at 8:00 a.m. This is not extreme stuff. Now, by the end of that study, those same people had reduced their body weight, their belly fat, their blood pressure, and their cholesterol, having encountered not a single calorie. They improved
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basically every single cardiovascular risk factor purely by changing the timing of their meals. Now later work has actually gone on to show this same pattern of benefits. And Professor Panda's lab went on to demonstrate that timerestricted eating like this actually
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reshapes gene expression right across your entire body. I hope I'm getting across just how important and influential this sort of eating is.
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Let's just add up what this one change is doing inside your body. So, we're talking about better blood sugar control that lowers your risk of type 2 diabetes. We're talking about restored nocturnal blood pressure, which lowers your risk of stroke and heart failure.
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We're talking about lower chronic inflammation levels, which lowers your risk of pretty much every disease that we know of, including cancer. We're talking about better sleep, lower cortisol, better daily metabolic flexibility. All of these stack up on top of one another and the cumulative
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effect on your risk of dying early is far greater than any single one of these in isolation. And that's exactly what medications do. They work on one tiny small process on its own. They don't work on everything altogether. And the
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way I try to think about all of this is to think of disease as a row of tipping points. So you have a tipping point for diabetes. You've got a tipping point for high blood pressure becoming dangerous.
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You've got a tipping point for your arteries becoming inflamed enough to start failing and causing heart attacks.
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You've got a tipping point for your cells losing the ability to clear their own damage. And through your 40s and 50s and 60s, you very quietly drift towards each of those tipping points. And bad health is essentially the moment that
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one of them gets crossed. Now, a tiny daily change like this, a daily nudge in the right direction might only push you back a millimeter or so from those edges. But the thing is here, the same tiny nudge does that to several edges at
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once. So, multiply that by 10 years and 20 years and 30 years of consistent practice doing these things all the time. Then a habit that looks insignificant on any single day turns out to keep you on the safe side of all
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of those tipping points simultaneously. Well, the people that do nothing for their health slowly crosses those tipping points one by one as they get older. This is why something as simple as not eating in the 3 hours before bed
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and giving yourself this proper fasting window overnight really does lower your risk of an early death. It's not because this habit on its own is performing a miracle or is super powerful on its own.
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It's because it's quietly working on four or five or six different disease processes at the same time every single night for the rest of your life. And the most powerful thing about it, as with every habit I talk about, is the amount
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of time you actually do it for. So, with all of that said, you've got to try and finish your last meal at least 3 hours before you go to bed. So, your stomach is pretty much empty by the time you lie
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down. Try and aim for an overnight fast of at least 14 hours, which is the threshold where the metabolic benefits really start to kick in. So, if you finish eating at 7 in the evening, then simply don't eat again until 9 the next
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morning. And because you spend most of those hours actually asleep, it's far less daunting than it first sounds, you don't have to think about it because you're unconscious literally for most of that fasting window. But you've got to
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be honest with yourself about the start, though. So the first week or two, you will feel hungry in the evening or first thing in the morning because your body has been trained to expect food at those times of the day and it complains when
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it doesn't arrive. But that hunger really does fade pretty quickly though. Usually within a couple of weeks. And what you discover on the other side of that is that you honestly don't need as much food to get you through the day as
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you thought you did. And this is because your appetite will naturally settle down. Your cravings will start to settle down and the meals start to feel more like actual events rather than just like a steady stream that you barely notice
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where you graze constantly throughout the day. The great thing about this though is that it doesn't ask you to give up any particular food. It doesn't involve weighing or measuring anything and it doesn't cost anything. If anything, you will spend less money
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because you're buying less food. The effects on your blood pressure and your blood sugar and your weight and your reflux symptoms like I had and your sleep quality and your long-term disease risk, these are absolutely remarkable for something so simple. Remember, your
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body was built to expect a daily rhythm of feeding and fasting. And given it back, that overnight rest is one of the most cost-free, side effect free, high impact things that you can do for your long-term health. So, if you're not
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already doing this, then just try it for a couple of weeks and see how you feel.
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I guarantee that the vast majority of people who try this will feel better about themselves. You'll have better sleep. You'll feel less hungry. you'll be more rested during the day and you will know that you're doing something really powerful for your long-term
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health. So, I really hope you found that video useful and helpful and you got some really good tips from it. If you did, then please just give it a thumbs up and subscribe to the channel as well.
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I promise you it's completely free. It doesn't cost you a penny and it really does help this channel grow and hopefully reach more people who can benefit from this advice.
Topics:circadian rhythmchrononutritionlate-night eatingblood sugar controlinsulin resistanceacid refluxhealth habitsDr Alexfastingsleep improvement
