Eat More Calories in the Morning than the Evening

Eat More Calories in the Morning than the Evening
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Why are calories eaten in the morning less fattening than calories eaten in the evening?

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Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Why are calories eaten in the morning apparently less fattening than calories eaten in the evening? One reason is that more calories are burned off in the morning due to diet-induced thermogenesis. That’s the amount of energy the body takes to digest and process a meal, given off in part as waste heat. If you take people and give them the exact same meal in the morning, afternoon, and night, their body uses up about 25 percent more calories to process it in the afternoon than night, and about 50 percent more calories to digest it in the morning. That leaves fewer net calories in the morning to be stored as fat.

Let’s put some actual numbers to it. A group of Italian researchers randomized 20 people to eat the same standardized meal at 8am or at 8pm, and then a week later had them all come back in to do the opposite. So, each person had a chance to eat the same meal for breakfast and for dinner. After each meal, the subjects were place in a “calorimeter” contraption to precisely measure how many calories they were burning over the next three hours. The researchers calculated that the meal given in the morning took about 300 calories to digest, whereas the same meal given at night used up only about 200 calories to process. The meal was about 1,200 calories, but given in the morning, it ended up only providing about 900 calories, compared to more like 1,000 calories at night. Same meal, same food, same amount of food, but effectively 100 fewer calories. So, a calorie is not just a calorie. It depends when we eat them.

Why do we burn more calories eating a morning meal—is it behavioral or biological? If you started working the graveyard shift, sleeping during the day and working all night, which meal would net you fewer calories? Would it be the “breakfast” you had at night before you went to work, or the “supper” you had in the morning before you went to bed? In other words, is it something about eating before you go to sleep that causes your body to hold on to more calories, or is it built into our circadian rhythm, where we store more calories at night regardless of what we’re doing? You don’t know, until you put it to the test.

Harvard researchers randomized people to identical meals at 8am versus 8pm while under simulated night shifts or day shifts. And regardless of activity level or sleeping cycle, the calories burned processing the morning meals was 50 percent higher than in the evening. So, the difference is explained by chronobiology; it’s just part of our circadian rhythms to burn more meal calories in the morning. But why? What exactly is going on?

How does it make sense for our body to waste calories in the morning when we have the whole day ahead of us?

Our body isn’t so much wasting calories as investing them. When we eat in the morning, our body bulks up our muscles with glycogen, which is the primary energy reserve our body uses to fuel our muscles. But this takes energy. In the evening, our body expects to be sleeping for much of the next 12 hours, so rather than storing blood sugar as extra glycogen in our muscles, it preferentially uses it as an energy source, which may end up meaning we burn less of our backup fuel (body fat). In the morning, however, our body expects to be running around all day, so instead of just burning off breakfast, our body continues to dip into its fat stores while we use breakfast calories to stuff our muscles full of the energy reserves we need to move around over the course of the day. That’s where the “inefficiency” may come from. The reason it costs more calories to process a morning meal is because instead of just burning glucose (blood sugar) directly, our bodies are instead using up energy to string glucose molecules together into chains of glycogen in our muscles, which are then just going to be broken back down into glucose later in the day. That extra assembly/disassembly step takes energy—energy that your body takes out of your meal, leaving you with fewer calories.

So, in the morning, our muscles are especially sensitive to insulin, rapidly pulling blood sugar out of our bloodstream to build up glycogen reserves. At night, though, our muscles become relatively insulin resistant. Our muscles resist the signal to take in extra blood sugar. So, does that mean you get a higher blood sugar and insulin spike in the evening compared to eating the exact same meal in the morning? Yes. In that 100-calorie difference study, for example, blood sugars rose twice as high after the 8pm meal compared to same meal in the morning. So, shifting the bulk of our calorie intake towards the morning would appear to have a dual benefit—more weight loss, and better blood sugar control.

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Image credit: Kristina DeMuth. Image has been modified.

Video production by Glass Entertainment

Motion graphics by Avocado Video

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

Why are calories eaten in the morning apparently less fattening than calories eaten in the evening? One reason is that more calories are burned off in the morning due to diet-induced thermogenesis. That’s the amount of energy the body takes to digest and process a meal, given off in part as waste heat. If you take people and give them the exact same meal in the morning, afternoon, and night, their body uses up about 25 percent more calories to process it in the afternoon than night, and about 50 percent more calories to digest it in the morning. That leaves fewer net calories in the morning to be stored as fat.

Let’s put some actual numbers to it. A group of Italian researchers randomized 20 people to eat the same standardized meal at 8am or at 8pm, and then a week later had them all come back in to do the opposite. So, each person had a chance to eat the same meal for breakfast and for dinner. After each meal, the subjects were place in a “calorimeter” contraption to precisely measure how many calories they were burning over the next three hours. The researchers calculated that the meal given in the morning took about 300 calories to digest, whereas the same meal given at night used up only about 200 calories to process. The meal was about 1,200 calories, but given in the morning, it ended up only providing about 900 calories, compared to more like 1,000 calories at night. Same meal, same food, same amount of food, but effectively 100 fewer calories. So, a calorie is not just a calorie. It depends when we eat them.

Why do we burn more calories eating a morning meal—is it behavioral or biological? If you started working the graveyard shift, sleeping during the day and working all night, which meal would net you fewer calories? Would it be the “breakfast” you had at night before you went to work, or the “supper” you had in the morning before you went to bed? In other words, is it something about eating before you go to sleep that causes your body to hold on to more calories, or is it built into our circadian rhythm, where we store more calories at night regardless of what we’re doing? You don’t know, until you put it to the test.

Harvard researchers randomized people to identical meals at 8am versus 8pm while under simulated night shifts or day shifts. And regardless of activity level or sleeping cycle, the calories burned processing the morning meals was 50 percent higher than in the evening. So, the difference is explained by chronobiology; it’s just part of our circadian rhythms to burn more meal calories in the morning. But why? What exactly is going on?

How does it make sense for our body to waste calories in the morning when we have the whole day ahead of us?

Our body isn’t so much wasting calories as investing them. When we eat in the morning, our body bulks up our muscles with glycogen, which is the primary energy reserve our body uses to fuel our muscles. But this takes energy. In the evening, our body expects to be sleeping for much of the next 12 hours, so rather than storing blood sugar as extra glycogen in our muscles, it preferentially uses it as an energy source, which may end up meaning we burn less of our backup fuel (body fat). In the morning, however, our body expects to be running around all day, so instead of just burning off breakfast, our body continues to dip into its fat stores while we use breakfast calories to stuff our muscles full of the energy reserves we need to move around over the course of the day. That’s where the “inefficiency” may come from. The reason it costs more calories to process a morning meal is because instead of just burning glucose (blood sugar) directly, our bodies are instead using up energy to string glucose molecules together into chains of glycogen in our muscles, which are then just going to be broken back down into glucose later in the day. That extra assembly/disassembly step takes energy—energy that your body takes out of your meal, leaving you with fewer calories.

So, in the morning, our muscles are especially sensitive to insulin, rapidly pulling blood sugar out of our bloodstream to build up glycogen reserves. At night, though, our muscles become relatively insulin resistant. Our muscles resist the signal to take in extra blood sugar. So, does that mean you get a higher blood sugar and insulin spike in the evening compared to eating the exact same meal in the morning? Yes. In that 100-calorie difference study, for example, blood sugars rose twice as high after the 8pm meal compared to same meal in the morning. So, shifting the bulk of our calorie intake towards the morning would appear to have a dual benefit—more weight loss, and better blood sugar control.

Please consider volunteering to help out on the site.

Image credit: Kristina DeMuth. Image has been modified.

Video production by Glass Entertainment

Motion graphics by Avocado Video

Doctor's Note

You thought dual benefits sounded good. Stay tuned—triple benefits are next! I’m going into more on circadian rhythms next with:

In the last few videos, I’ve been focusing on why the science points to loading your calories towards the beginning of the day:

If you haven’t yet, you can subscribe to my videos for free by clicking here.

73 responses to “Eat More Calories in the Morning than the Evening

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  1. Hi! Could you go into more detail about the data on being more insulin sensitive in the morning? It is well known among those with type 1 diabetes that there is greater insulin resistance or a greater need for insulin at breakfast compared to eating the same meal in the evening. Would love to hear Dr. Greger’s thoughts on this.

    1. From the video, it seems to me that the muscles are taking in more glucose for storage in the mornings, requiring insulin to do so. In the evenings, the muscles are taking up less, requiring less insulin.

    2. Amber, what you say is true, not only for type 1 diabetics, but also for type 1.5’s.
      I.E. anyone who biologically doesn’t make enough insulin to regulate the natural morning spike in blood glucose. That’s why diabetics who have this problem are told to eat fewer carbs in the morning. They do better with a higher protein, lower carb meal like beans and greens in the morning. Soybeans, tempeh, etc. foods that are naturally higher in protein and healthy fat are excellent morning foods.

      Many type 1’s and 1.5’s also find working out first thing in the morning can raise blood sugar unless it’s a really long, hard workout.
      They tend to do better with an afternoon, early evening workout instead.

    3. More good news for me, the earliest riser in the family! Up at 4 breakfast between 5-6. Body at work.
      Thanks for the encouragement.

    4. Hi Amber. As a mom of a type 1 diabetic I had the same reaction. I think the key is Dr. Greger did not say we are more insulin sensitive in the morning; he said we have a lower blood sugar spike after eating. We still are more insulin resistant in the morning due to all the high levels of hormones like cortisol and glucagon floating around, it’s just that we produce more insulin to get the glucose in the cells. That’s why a type 1 diabetic raises basal insulin in the morning, to cover the glucose released from the liver. This will keep blood sugar stable all morning long without eating. Then if they eat, they’ll usually need to give a lot more insulin for the same amount of food eaten in the evening.

    5. Actually, looking into this further, it appears quite complicated. This review article concludes that diabetics and obese individuals have a different circadian rhythm than non diabetics.

      “Taken together, these findings suggest that glucose tolerance exhibits circadian variation, with poorer glycemic control in the evening and at night in healthy adults. Diurnal rhythms in β-cell responsiveness, peripheral insulin sensitivity (influenced by both internal and circulating factors), insulin clearance, and glucose effectiveness drive these diurnal rhythms in glucose metabolism, whereas hepatic insulin sensitivity may play a lesser role. However, these rhythms are attenuated or phase-delayed in obese and diabetic adults, suggesting that altered circadian rhythms may be a cause or consequence of many metabolic diseases.” https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5995632/

  2. I have a silly question. What if your circadian clock is messed up, and morning is not morning. For instance one is pre disposed to getting up at 9-10 am? Eats between 10-11, Is that still considered morning ?

  3. One thing I don’t understand, because it doesn’t jibe with personal experience. My daughter is Type 1 diabetic, and she requires twice as much insulin in the morning than at night, for the same amount of food. Her endocrinologist said this is very common as we require more insulin in the morning due to high cortisol levels.

    1. Julie, yes, the rise in cortisol causes the liver to make glucose. Without the ability to counter this with insulin, type 1’s and 1.5’s blood sugar goes too high. Morning meals for these diabetics should be higher protein, lower carb. See Barb’s post above yours.

  4. Despite some advance there is may be if I would eat more in the morning then in the evening – my live quality would go down – sorry. Why? My wife and me are going early out of the house for work in the morning, no time for a relaxed breakfast… so we use the time we have togehter in the evening (to cook and eat together) … if I earn a pound or two more on my hipps – never mind, that’s worth. ;-) We are on a whole food, plant based, low fat diet for 10 years now and would never go back. I run my bike for nearly 9.000 km every year with only one leg, my wife is running as often she can. So I think the chance to get diabetes typ 2, to get obesed or something other odds is really low.
    There are much mor other risks for my life, how I learn at this time by reading the book “How Not To Diet”.
    Thank you so much for your work, my friend Dr. Michael Greger!

  5. Thanks for all this great information but I would so much prefer if I could just read the exact same information on the blog instead of watching the video. Reading the exact same info is so much faster, easier to retain, and I actually find it really annoying to watch him speak with all his bizarre little affects. Why go to all that extra work of making a video if you could just easily write the same info?

    1. that was my observation too-he has the pause as he speaks-so he speaks fast a few words and then he pauses or hesitates-and it agitates me. It is an east coast speak pattern and he is probably not even aware he does it. He is well spoken and does his research, so it is unfortunate that by speaking with this speech problem he isn’t aware that it is off putting to listen to him. I tried to listen to him read the audio book of How Not to Diet and he was even worse-he was trying to read it like Howard Stern-I had to turn it off.
      That being said, I think he’s probably a really nice guy and engaging and funny-he just needs a speech therapist to help with his speech ticks.

      1. Alex, this delivery of his is likely less a “tick”, and more a choice. Its likely endearing to some, annoying to others. Its implied irony is meant to be unique and entertaining I’m sure – remember he was a Professor too, tasked with getting college students interested in vegetables. I’m quite sure he is aware and his delivery, perhaps even not so keen on public speaking early in but compelled by the importance of his message. Too, it sets him apart from others, and I’d be quite surprised if he ever changes it. It’s part of his lighthearted personality no doubt and we all know it has brought him all the way here. So we can all be talking about vegetables rather than eating hamburgers.
        That said, my wife feels the same way! lol She also however, comments on TV personalities and their clothes, and noses, etc…a bit if ADHD really. Gets distracted, focusing on delivery and visuals or sounds, instead of content.

        My solution for her was: Read his books and transcripts and listen to your own wonderful voice, et voila! Problem solved. :)

  6. Ghrelin is the hormone that tells the brain that we are hungry, leptin is the one which tells us we are satiated. Consumption of processed food causes increased production of the former, while whole plants stimulate production of the latter.

    Junk food is a vicious cycle for a number of reasons.

    1. Navy,
      So you are saying if one consumes factory based business foods, a voice in your head with say have more, more, more.
      But if you have a natural item like a plain apple, a voice in your head will not say, have a 2nd apple and a 3rd apple and a 4th apple?
      I think Cole Kutz said this 25 years ago. Some people think he owned a deli, but he owned a movie theatre. When he passed,
      funeral services were at 2, 5 and 8 pm.

  7. Dr. Greger,

    I actually saw this study cited in a blog for acne called http://www.acneeinstein.com (Author: Seppo Puusa).
    Anyways, the reason this appeared there was because this Italian study also looks at blood glucose levels after a meal, along with the levels of other important bodily responses that appear in the form of graphs. This is important because this spike in blood glucose can have the domino effect on the hormone insulin that ultimately leads to acne, specifically in patients that have issues with hormone-induced acne.

    I am Vegan. I have followed the advice that the blog suggested and have seen great results. Before i followed the big breakfast/small dinner advice, i was breaking out like crazy and didn’t understand why, especially because of how clean i eat. At the time, however, i wasn’t concerned with how much in carbs i would eat in a day. Currently, i follow a high fat, slightly carbohydrate-restricted vegan diet that has not given me any breakouts (i used cronometer to determine what would be the most ideal). What i would like to know is if it is possible to eat a high carbohydrate vegan diet and avoid these blood sugar/insulin spikes by following this way of eating? Or is being high carb vegan not recommended if one has hormone related acne. Mind you, i am very conscious of eating slow-digesting carbs like beans, whole grains, etc. NO white potatoes, flours, high amounts of sugar, etc.

    I very much believe in a plant-based lifestyle and would like your input on this topic or possibly even a video that touches base on how this “big breakfast/small dinner” idea can tie into working on preventing acne while following a well-rounded vegan diet. Thanks in advance. I very much enjoy the educational and motivational content of your website.

    1. If you peel white potatoes and cook them in fat they are one of the worst foods. If you keep them unpeeled and cook them without fat they are one of the best foods on the face of the earth. There are two foods, either of which constitutes a complete diet for humans. Potatoes and sweet potatoes. See “The Starch Solution” by Dr. John McDougall.

    2. Leo,

      When you say “high fat” do you mean avocado, nuts, and seeds or oils?

      People can eat high carbohydrate and not have blood sugar spikes, but it may not work if you are using oils.

      For instance, my Keto friends have higher fasting blood sugar levels and that is from their Keto diet. Dr. Greger explains that in his Is Keto Good for Diabetes series.

      1. Deb,

        Yes, now i only include whole food sources of fats. However, i will say that when i was breaking out i was indeed deliberately adding cold pressed canola oil in my food. Maybe that was causing some kind of spike in my blood glucose and insulin which subsequently lead to more acne even though the sources of carbohydrates i was eating were only from legumes and whole grains.

        Now i have another question: Does this video mean that ONLY calories are to be taken into account when we are creating meals for breakfast, lunch and dinner? Or does this video also suggest that the amount of carbohydrates should maybe be kept to a minimum ONLY for dinner due to the insulin resistance factor?

  8. I love this video. I’ve already listened to How Not to Diet in audiobook format, but this point is so interesting to me that the video was also very engaging to watch.

    For some reason, I was also enjoying the new format in this particular video. Yes, I had to pause the video 2 or 3 times to read the pages of the journals you displayed on the screen, but I did that in the previous format videos as well. Other than that final-moments ‘zooming around’ of Dr. Greger at the end–repositioning him to have the paper on the right and graphics on the left–I enjoyed all the graphics and Dr. Greger speaking, and didn’t find them intrusive or distracting. Perhaps I am growing used to the new format, or perhaps this video is just less hectic, in the vein of the graphics-and-texts-only videos of yesteryear.

    Anyway, I wanted to let you know that I really liked the video, and the science is astounding. I’ve been eating more at breakfast and less at dinner–and sometimes only eating a large combined lunch/dinner as a second and final meal of the day (which I refer to as linner or dunch, haha) and I can tell the difference. I have always preferred having a large breakfast, but as the rise of intermittent fasting has taken hold of our national zeitgeist, I figured that breakfast could be dispensed with as the least painful meal, psychologically, for me to miss. Some benefits I’ve enjoyed are: 1. more energy in the morning; 2. even better digestion; 3. better sleep.

    Thanks again.

    1. Laughing at the dunch.

      Yes, some of these newer format videos have been better. I do think there is a bit of getting used to them, but when there are simpler visuals, it seems to work. I honestly don’t always go and look at the journals in this format, where I always did in the older format, but I agree that I liked this one.

      I still don’t quite understand when the night shift workers should eat breakfast.

      It is almost 5 in the morning and I think I will try eating some oatmeal and then going to bed.

      I guess I won’t know unless I try it out.

      1. dr cobalt:

        I’m about 20 minutes into the PBS documentary. Yes, very interesting. So far it’s about tampered-with food products riddled with chemicals and other garbage, so I don’t see a connection to a “vegan” diet so far.

        Anyway, as we know, those who call themselves vegan can eat pure crap and think it’s a healthy diet. Better to follow a whole foods, no-processed diet.

        1. You’re right on both counts. I am a WFPB devotee mostly because of this website.

          As far as the TAE story goes, with the exception of some canned vegetables mentioned early on (adulterated by copper sulfate), nearly all the food products in the expose that were adulterated, preserved, or sold as tainted were of animal origin – meat, dairy, eggs, butter. (Coke was another exception – also of non-animal source.) And we who tune-in to NF.org regularly know that this kind of industry deception, fraud, and lobbying still goes on today. NF.org got me away from animals products; I call myself a vegan today, even if I don’t carry a PETA card or a Sierra Club membership in my non-leather wallet.

          But this TAE video might have pushed me over the top too.

    1. I just started watching the PBS documentary, “The Poison Squad,” and my husband, sitting nearby, is listening to it.

      His comment: “For a while, the FDA regulated food manufacturers. Now, big food corporations regulate the government.”

      One area that is still the Wild West, which most people don’t realize, is the supplement industry. And that includes vitamins. Let’s see: false and misleading claims are regulated by the FTC. But the FDA does not oversee supplements; there is no requirement to prove them safe or effective before they go on sale. The supplement industry was excepted from FDA regulation. If problems arise, and these problems are both detected and reported (some don’t show up right away, and it’s tough to determine the source), the FDA can step in to investigate. Any penalties seem like a slap on the wrist to me. And, as Dr. Greger has pointed out, supplements may contain more, less, or none at all what is claimed on the container label; they may be adulterated with drugs, and they may be contaminated by other materials, pathogens, and heavy metals, some of which are toxic — none of these adulterants or contaminants are listed on the label. And who knows how they interact with drugs that some folks already take?

      1. And food tampering, among other problems with our food industry, is still occurring. Watch the series “rotten” on Netflix. Honey is STILL being adulterated with sugar syrup, or other honeys, etc. The miscreants stay one step ahead of the regulators. But that’s not all. Happily, I don’t eat animal products — except honey. But I do eat garlic, and chocolate, and some other foods.

      2. Faced with the inability, or refusal of the USDA and FDA to protect the American people you want them to ‘regulate’ supplements?
        For many of my patients, targeted high-quality supplements do a better job for them than pharmaceutical drugs.

        1. Both supplements and pharmaceuticals are ‘drugs’ in the struct sense of the term.

          Supplements are notorious for often containing contaminants, not containing the ingredients/amounts they say they do and inconsistent dosing.

          I agree with Dr J that we would benefit from greater regulation and oversight of the supplement industry.

        2. Marilyn Kaye,

          Oh, yes, I absolutely DO want the FDA to regulate supplements, for many reasons. They do a far better job than doing nothing; check your history of drug regulation in this country. (eg: why do you think that thalidomide babies were not born in this country? Because the FDA looked at the effects of this drug coming out of England, and stopped it from being used on pregnant women in this country. Actually, it was one very brave and courageous doctor at the FDA responsible for this.)

          “In the current Wild West of lax dietary supplement regulations, a supplement can be marketed without any safety data at all and the manufacturer is under no obligation to disclose adverse effects that may arise…The president of Matabolife International, a leading seller of ephedra, assured the FDA that the company had “never received one notice from a consumer that any serious adverse health event had occurred.” Liar. In reality, Metabolife had received thirteen thousand health complaints, including reports of serious injuries, hospitalizations, and deaths.” (“How Not to Diet,” p 494)

          I have no idea what kind of “targeted high-quality supplements” you are recommending to your patients, but if they are safe (but how would you know this, in the absence of data? Some adverse effects can take a while to show up) and effective (again, how would you know this?), and they actually contain what they claim, and aren’t adulterated or contaminated, then they should have no problem in a regulated environment, right?

          1. ps: Actually, I read aloud the quote in my comment above to my husband, who noted “Perhaps the consumers weren’t filing their adverse effects, but their health care providers, lawyers, and others were.” I wonder…

    1. @mm , I was prone to thinking similarly.. But here’s what I came up with. So, I think, that Dr. Gregor doesn’t BS just to make content. I don’t mean to say here, that this is what you are implying, but rather that his sharing of this info isn’t random, or just to fill space. So as a trusted subject matter expert, I believe he shares these results largely because he feels its relevant to our health, and more importantly, because the studies are designed correctly. That goes to what I believe so far are his own ethics. I am not a scientist, nor doctor, but my understanding is that even small studies, as long as they are truly designed correctly, do generate a lot of usable information, just like large studies with poor design can give an interested industry PR firm the results it wants. etc..

      I suppose I am replying because there is an air of doubt in your post and I too question things, and had thought, the second he mentioned it, that a 20 person study could perhaps be insufficient to cite and extrapolate substantive meaning and advice.

      Maybe a doctor or researcher here, or Dr. Gregor himself can chime in on the question of citations of evidence based on small studies?

      Its pretty cool you brought this up though, and I think now Id like to see the Doc do a video on what is a truly well designed study, and what is not (more obvious I think), and what the minimum number of pparticipants is, that can be sufficient for an official, scientific study… if designed well?

      Good stuff!

  9. Back on topic, I’ve always been curious about this…
    For instance, What if I travel to a time zone which is 12 hours away? When is my circadian “morning”? So, if its based on sunrise/sunset, what about parts of the world where its sunny 20 hours a day or dark most the day? I am under the impression that circadian instruction is flexible, as in new time zone residency creates new “instructions” eventually, so then will a graveyard shift alter the circadian instructions if the shift is adhered to for a long period of time? Months or years for instance? Any thoughts on the strength of cultural circadian instruction as in, people of the East may observe different circadian rules, or people in cities may stay up late, wake late, etc…?
    Relating it all back to the calories burned based on circadian tendencies, are these things I mention just outliers, or relevant? Meaning just eat more in the morning, wherever you are, including during travel?
    This is the coolest site I know of right now and I am loving getting healthy and informed because of it. Also because of the the two catalysts that simultaneously brought me here when I binge-watched them back to back, then randomly found Dr. Gregor: Forks over Knives, Game Changer.

    1. jazzBass, what you say is very relevant. Type 2 diabetics who do rotating shifts find regulating blood sugar very difficult.
      Also, not everyone has the same inborn circadian rhythm.

    2. #jazzBass – holt on for a while, sit down and think again about you issue. The humans are humans and for this they have legs to walk, not wings to fly… so, from this point of view, what do you think how long you would walk to reach a country that has 12 h different to your home? In this time your circadian goes with you, because there will be only minutes per day different to the place the da before. People are not designed to travel by car, airplan or train… on the other hand, we are addicts of the sun, the clock is only a technical tool invented by the human, that means, the sun has more inpact of your circadian then other things.
      I don’t know if I could explain it understandable but I hope, if not, I can explain it very good in Germany ;-)

  10. JazzBass, from the studies I have been reading (following Dr Greger’s linked sources under Sources tab). for this series, a couple of points were made. Someone like an airline pilot who crosses time zones regularly and plays havoc with their circadian rhythm is more likely to
    suffer health repercussions than someone who doesn’t. Also, a person that moves to a different place on the planet would eventually adjust because light and food are two of the ‘inputs’ that set the events in motion biologically. A person who works night shift however is at odds with their circadian rhythm as I understand it. More is to come on the series, including a video about shift workers.

    Dr Greger does regularly talk about what makes a good study and the different study types and features. He presents a few (of the great many studies they look at) studies in these videos that are both interesting and representative of the science. As I understand it, the sources section for his new book, How Not to Diet, is so huge they had to make it available online.

  11. Noted that this meal was 1200 calories, that is an enormous amount.
    I was taught that no more than 500 calories should be consumed at any one meal. 500 calories was assumed to be the maximum amount used, the excess being converted to body fat.
    Can no longer find that study, anyone know if this is still believed to be true?

  12. I have two follow up questions related to our circadian rhythms:

    1. I read about a study recently that suggested taking heart medication at night was much better?

    2. Is exercising in the morning better for you.

    Thanks~ fascinating topic!

    1. Wendy, as far as medication goes, you may have received an information handout at the pharmacy with your new prescription. If not, ask the pharmacist, and certainly check with your doctor. It depends on the type of medications and what else you are taking. I switched to taking aspirin, bp med (1), and statin at night time.
      If a person is taking more than 1 bp med then the doctor or pharmacist should advise you.

      https://www.usatoday.com/story/news/health/2019/10/23/blood-pressure-medicine-night-may-lower-heart-attack-and-stroke/4071439002/

      https://www.rd.com/health/medication-timing/

      I believe there is more info about exercise coming up, but the short answer is, it depends. Marilyn Kaye was mentioning that in some people, morning exercise can raise blood sugar. Dr Greger says before breakfast exercise is good, but there is more to come on that subject.

        1. Wendy, yes, ty, same study as in the links I posted for blood pressure meds. Your question was about “heart medications” though, and that covers a huge range of medications where the prescriber is generally specific about the directions of when to take them. For blood pressure meds, some people take 2 , 3, or more drugs for this purpose and their doctor would be the one to say which of the prescriptions are best taken at night. (I take a beta blocker at night with good result.) Diuretics would probably be better taken in the day to avoid running to the bathroom all night.

          1. Thanks. I guess I should have been clear that I am not asking for medical advice, I just think it is interesting how timing medications, similar to caloric intake, can drastically effect things like mortality.

            1. Wendy, I think this is the most fascinating topic that Dr Greger has talked about that I have seen in the ten years I’ve followed NF. It’s fantastic what small changes to bring ourselves in line with our circadian rhythm can do!

              I have seen all kinds of studies on different medications, chemo, food, exercise, sleep, obesity, dementia, you name it!

              In the last six months I have made some (what I think of as minor) changes in lifestyle habits that ended up having profound difference in my health. The impact feels greater than when I adopted wfpb even years ago.
              I don’t really understand why people don’t leap at the chance to iimpact their health in such a positive way!

  13. I am still processing this one.

    I guess “When does morning begin?” is the question people who are up all night have trouble processing.

    If it is almost 4:30 right now, and I haven’t gone to bed yet, can I eat breakfast now and go to sleep and is that eating in the morning or are we still at night?

  14. Hi. Should I advise my son so consume most of his calories in the evening? He is 29 and tries to eat healthily inc lots of plant based foods. He doesnt have dairy and avoids processed foods. But he exercises a lot and also wants to put on weght but finds it difficult. There is only so much avocado etc you can eat in a day.

    1. Lynn,

      Someone recommended looking at the vegan weight lifting videos and learning from that community because they focus on building muscle.

      Learning from vegan weightlifters isn’t a bad concept.

  15. Dr Greger,
    I heard you on the art of aging seminar the day before yesterday. It was good. The speakers at the seminar focused on all aspects of health. It is difficult for me to keep attention on health messages in general, because the overwhelming focus on weight loss. I know the majority of the people are interested in weight loss strategies, but some of us couldn’t care less, because we eat for optimum health and that automatically regulates our weight to ideal. I believe that if you just let people know that healthy diet and lifestyle brings the bonus of right weight and more energy and well being, then go ahead and tell more about how to live well, it would be productive for all of us.

  16. So, does Dr. Greger on traveling around the world know whether your body knows that you traveled to Poland and tell the cells, “Yes, it is too morning.”

  17. Airline pilots would have to go nuts figuring out which morning they are supposed to be eating.

    Oops, they had too many mornings and gained 3 pounds.

  18. If they travel West, they get to eat this many meals, but if they travel East, they suddenly find out they missed the window and have to intermittent fast.

  19. Better insulin sensitivity in the morning implies that it’s better to eat your carbs in the morning. Is there a better time to eat fats?

  20. I keep trying to eat more in the earlier part of the day but I just can’t do it! I force a little food down or a green smoothie for breakfast, then I can eat equivalent to half a sandwich for lunch. My appetite just won’t wake up until 6:00pm and then BOOM I’m hungry for a full meal.
    Any ideas how I could change this viscous cycle of eating later in the day which makes me not hungry enough the next morning?

  21. Can’t get myself to eat more earlier in the day because I just don’t have an appetite until 6:00pm. Any ideas how I can change this?

  22. Hi Dimitra Arneson, thanks for your question. It is important to do a bit of thinking and investigating what is your daily habit and routine? Does your body function well with this eating pattern? your physical activity level? If this routine is not helping may be having a light meal at night to adjust your body into carving for bigger breakfast? Having some food that boost the appetite during morning and lunch time. Also having enough fiber in the diet to keep the digestive system flowing smoothly. These are few suggestions that might be useful to you.

    1. Dear Spring 03, I know what you are suggesting but I just can’t figure it out. I’ve tried eating oatmeal and fruit for breakfast sometimes and then eggs another morning. I get full very fast in the morning and at lunch time. Following the Daily Dozen closely. I’m not diabetic and blood tests show no prediabetes either. But if I don’t eat late at night, I can’t sleep at night and wake up after a couple of hours between 11:30pm and 1:00am and have to eat something to be able to fall asleep.
      I know I’m weird.

  23. Can one of the forum moderators or someone else with nutrition expertise please address the Gastropod podcast’s take on the science of skipping breakfast? Here is what they said (https://gastropod.com/breakfast-champions/):

    “TO SKIP OR NOT TO SKIP

    Much has been made about the importance of a good breakfast to a healthy lifestyle. It gives you energy to start your day, according to conventional wisdom, and scientific studies conducted a decade ago had proclaimed that eating breakfast was the key to maintaining a healthy weight.

    “Breakfast skippers are plagued with well-meaning spouses, partners, family members, and friends, all insisting that they should eat something in the morning. But, according to nutrition scientist P. K. Newby, that advice was based on what’s known as observational studies, in which scientists follow groups of people and observe the outcomes. The result had seemed to indicate that people who lost weight or maintained a healthy weight ate breakfast. The problem, Newby told us, is that those studies didn’t isolate breakfast as the important factor. It could be, she says, that those who lost weight also exercised more, or one of dozens of other variables.

    “Then, last year, a group of researchers at the University of Alabama published a study that took a more rigorous look at this question. They enlisted 300 participants and randomly assigned them to eat breakfast, to skip breakfast, or to simply go about their normal routine. After 16 weeks, they found no difference in weight loss among the three groups. Meanwhile, in a similarly controlled Cornell University study, people who skipped breakfast consumed fewer calories by the end of the day. And, in a smaller study at the University of Bath, people who skipped breakfast also seem to have consumed slightly fewer calories during the day, though they then expended slightly less energy.

    “Based on this new research, the bottom line, Newby says, is this: if you’re not hungry in the morning, there’s no harm in skipping breakfast when it comes to weight management. “It’s the what that is more important than the when, when it comes to breakfast,” she says, which also means that grabbing a sugary muffin, doughnut, or other pastry, just to eat something in the morning, is a worse idea than eating nothing at all.”

  24. So when should people who work overnight eat the majority of their calories. I’m an overnight ER doctor and my schedule will not be changing any time soon as I have worked nights for the past 10 or so years. I wake up at 3pm and return home at 7am the next day. Should I eat the majority of calories when I wake up or when I get home at 7am? If at 7am, what about it being so closed to when I go to bed? I usually eat at 4pm, maybe a snack at 10pm or midnight, then try not to eat too much after midnight.

  25. I am struggling with eating breakfast, lunch and dinner too late in the day (like at 2pm, 6pm and 9pm, respectively) but the habit seems to be cemented. I don’t want to gain weight and find that this schedule strangely helps stop me from giving into snacking cravings. I want to transition to a schedule more like what Dr. Greger recommends but don’t know want to feel like I’m starving, especially late in the day when my mood and energy level are usually at their troughs. I guess I’m open to suggestions or would be interested if anyone else has relevant experience.

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