Myth: Eat frequently to "stoke the metabolic fire"

Each time you eat, metabolic rate increases slightly for a few hours. Paradoxically, it takes energy to break down and absorb energy. This is the Thermic Effect of Food (TEF). The amount of energy expended is directly proportional to the amount of calories and nutrients consumed in the meal.

Let's assume that we are measuring TEF during 24 hours in a diet of 2700 kcal with 40% protein, 40% carbohydrate and 20% fat. We run three different trials where the only thing we change is the the meal frequency.

A) Three meals: 900 kcal per meal.

B) Six meals: 450 kcal per meal.

C) Nine meals: 300 kcal per meal.

What we'd find is a different pattern in regards to TEF. Example "A" would yield a larger and long lasting boost in metabolic rate that would gradually taper off until the next meal came around; TEF would show a "peak and valley"-pattern. "C" would yield a very weak but consistent boost in metabolic rate; an even pattern. "B" would be somewhere in between.

However, at the end of the 24-hour period, or as long as it would take to assimilate the nutrients, there would be no difference in TEF. The total amount of energy expended by TEF would be identical in each scenario. Meal frequency does not affect total TEF. You cannot "trick" the body in to burning more or less calories by manipulating meal frequency.


The most extensive review (http://www.ncbi.nlm.nih.gov/pubmed/9155494) of studies on various meal frequencies and TEF was published in 1997. It looked at many different studies that compared TEF during meal frequencies ranging from 1-17 meals and concluded:

"Studies using whole-body calorimetry and doubly-labelled water to assess total 24 h energy expenditure find no difference between nibbling and gorging".

Since then, no studies have refuted this. For a summary of the above cited study, read this research review by Lyle McDonald. http://www.bodyrecomposition.com/research-review/meal-frequency-and-energy-balance-research-review.html#more-1389

Earlier this year, a new study was published on the topic. As expected, no differences were found between a lower (3 meals) and higher meal (6 meals) frequency. Read this post for my summary of the study. This study garnered some attention in the mass media and it was nice to see the meal frequency myth being debunked in The New York Times.
http://www.ncbi.nlm.nih.gov/pubmed/19943985
http://www.leangains.com/2009/12/new-meal-frequency-study.html


Origin

Seeing how conclusive and clear research is on the topic of meal frequency, you might wonder why it is that some people, quite often RDs in fact, keep repeating the myth of "stoking the metabolic fire" by eating small meals on a frequent basis. My best guess is that they've somehow misunderstood TEF. After all, they're technically right to say you keep your metabolism humming along by eating frequently. They just missed that critical part where it was explained that TEF is proportional to the calories consumed in each meal.

Another guess is that they base the advice on some epidemiological studies that found an inverse correlation between high meal frequency and body weight in the population. What that means is that researchers may look at the dietary pattern of thousands individuals and find that those who eat more frequently tend to weigh less than those who eat less frequently. It's important to point out that these studies are uncontrolled in terms of calorie intake and are done on Average Joes (i.e. normal people who do not count calories and just eat spontaneously like most people).

There's a saying that goes "correlation does not imply causation" and this warrants further explanation since it explains many other dietary myths and fallacies. Just because there's a connection between low meal frequencies and higher body weights, doesn't mean that low meal frequencies cause weight gain. Those studies likely show that people who tend to eat less frequently have:

* Dysregulated eating patterns; the personality type that skips breakfast in favor of a donut in the car on the way to work, undereat during the day, and overeat in the evening. They tend to be less concerned with health and diet than those who eat more frequently.

* Another feasible explanation for the association between low meal frequencies and higher body weight is that meal skipping is often used as a weight loss strategy. People who are overweight are more likely to be on a diet and eat fewer meals.

The connection between lower meal frequency and higher body weight in the general population, and vice versa, is connected to behavioral patterns - not metabolism.

Replies

  • bdamaster60
    bdamaster60 Posts: 595 Member
    Ok I'm going to be honest I only read the first paragraph. But I agree.
  • babystepsforward
    babystepsforward Posts: 52 Member
    thats interesting thanks for posting
  • Alatariel75
    Alatariel75 Posts: 18,342 Member
    Thank you for that, ties right into my breakfast question!
  • Lyadeia
    Lyadeia Posts: 4,603 Member
    I don't eat 5 meals a day to "stoke the metabolic fire." I do it to keep myself satisfied and keep those hunger pangs away. I binge a lot more eating fewer meals.
  • sunlover89
    sunlover89 Posts: 436 Member
    I don't eat 5 meals a day to "stoke the metabolic fire." I do it to keep myself satisfied and keep those hunger pangs away. I binge a lot more eating fewer meals.

    It's good that you've found a method that works for you. I used to eat more frequent meal but it just made me more hungry and food obsessed! One of the most important things I've learnt, is to just ride the waves of hunger, they come and after 10 minutes and a glass of water, go. Different things work for different people :-) I'm not easily satiated when I do eat, so I'd rather have larger meals, less frequently.
  • eyvindur
    eyvindur Posts: 19 Member
    I always thought that eating regularly was just good for avoiding insulin spikes, cause those surely do make you fatter, right?
  • RosscoBoscko
    RosscoBoscko Posts: 632 Member
    I think the logic is that if you eat more small meals you are monitoring portion size far more, rather than if you eat less meals your portions are likely to be larger, due to hunger etc.

    Also from what I can see here, this doesn't take into account workout regime, as would this not effect the rate at which the calories are burned/stored in relation to the number of meals/quantity of calories consumed each time?
  • sunlover89
    sunlover89 Posts: 436 Member
    I always thought that eating regularly was just good for avoiding insulin spikes, cause those surely do make you fatter, right?

    It depends what you eat.

    If you eat chicken and broccoli every 3 hours, your insulin will spike slightly then go back to a normal state. If you eat a mars bar every 3 hours, your insulin will shoot up then crash, every 3 hours.

    If you eat chicken and broccoli every 6 hours, it will do the same thing, and your insulin levels should stay stable, if you arn't diabetic, drink enough fluids etc.

    I eat in a 6 hour window - 3pm-9pm, and i certainly don't eat mars bars. I break fast with cottage cheese and berries. This spikes my insulin slightly, but I don't crash, because I'm not eating a type of food that would cause a large spike and crash.

    I could eat white bread and butter with jam every 3 hours, even if it was within my calorie limit and be much worse off than eating two meals a day between 3pm and 9pm consisting of cottage cheese, fruit, lean meats and vegetables.
  • psuLemon
    psuLemon Posts: 38,432 MFP Moderator
    It might have been easier to just start with this study. It's a more direct, lol

    http://www.ncbi.nlm.nih.gov/pubmed/19943985


    "We conclude that increasing MF [meal frequency] does not promote greater body weight loss under the conditions described in the present study"
  • I never believed that eating more smaller meals throughout the day increased metabolism, I thought it was to keep one from getting too hungry. I am a snacker so I like to split up my meals. Calories are still calories no matter when they are consumed in a day.
  • sunlover89
    sunlover89 Posts: 436 Member
    It might have been easier to just start with this study. It's a more direct, lol

    http://www.ncbi.nlm.nih.gov/pubmed/19943985


    "We conclude that increasing MF [meal frequency] does not promote greater body weight loss under the conditions described in the present study"

    Oh, nice one :-P
  • sunlover89
    sunlover89 Posts: 436 Member
    I never believed that eating more smaller meals throughout the day increased metabolism, I thought it was to keep one from getting too hungry. I am a snacker so I like to split up my meals. Calories are still calories no matter when they are consumed in a day.

    There are a lot of people, especially body builders, who do believe this, and it irritates me when I hear them go on and on about it on the weights section at my gym!
  • psuLemon
    psuLemon Posts: 38,432 MFP Moderator
    I never believed that eating more smaller meals throughout the day increased metabolism, I thought it was to keep one from getting too hungry. I am a snacker so I like to split up my meals. Calories are still calories no matter when they are consumed in a day.

    There are a lot of people, especially body builders, who do believe this, and it irritates me when I hear them go on and on about it on the weights section at my gym!
    In all fairness, bodybuilders or those trying to build muscle generally do this for one main reason. The sheer amount of calories they need to consume is immense and eating them all in a short period of time isn't easy. My friend was trying to build 20 lbs of muscle and needed to consume 5000 calories. Needless to say, he can't do that in a few meals pending he eats healthier food.
  • tlc12078
    tlc12078 Posts: 334 Member
    I don't eat 5 meals a day to "stoke the metabolic fire." I do it to keep myself satisfied and keep those hunger pangs away. I binge a lot more eating fewer meals.

    It's good that you've found a method that works for you. I used to eat more frequent meal but it just made me more hungry and food obsessed! One of the most important things I've learnt, is to just ride the waves of hunger, they come and after 10 minutes and a glass of water, go. Different things work for different people :-) I'm not easily satiated when I do eat, so I'd rather have larger meals, less frequently.


    I noticed if I eat the 3 meals a day I tend to eat more. I am used to the big dinner meal and a small meal during the day, which I ate less. I felt fine, its weird how all our bodies work differently.
  • cupboard_stalker
    cupboard_stalker Posts: 62 Member
    Thank you for the most sensible post of the day! I love something based on scientifically tested fact and not generalised sweeping statements based on personal choice that are not backed up :)
  • MikeyD1280
    MikeyD1280 Posts: 5,257
    ..
  • kimastbury
    kimastbury Posts: 33 Member
    Sorry if this has already been covered, but I was wondering if anyone knows if there is any truth to the rumor that you will burn your food off faster if you train right before hand?
  • psuLemon
    psuLemon Posts: 38,432 MFP Moderator
    Sorry if this has already been covered, but I was wondering if anyone knows if there is any truth to the rumor that you will burn your food off faster if you train right before hand?

    Nope, what you are referring to is the metabolic window that people assume you need to eat in to replenish your body of it's nutrients. Below is a good thread on that. Ultimately, it is inconclusive if there actually is any benefit from eating post workout.


    http://www.myfitnesspal.com/topics/show/872189-alan-aragon-and-brad-schoenfeld-on-nutrient-timing
  • kimastbury
    kimastbury Posts: 33 Member
    Thank you!
  • Chief_Rocka
    Chief_Rocka Posts: 4,710 Member
    Also from what I can see here, this doesn't take into account workout regime, as would this not effect the rate at which the calories are burned/stored in relation to the number of meals/quantity of calories consumed each time

    Energy stores are constantly in flux, ot all averages out in the end.
  • Crankstr
    Crankstr Posts: 3,958 Member
    Whatever works for you...i dont like having smaller meals...never satisfying enough.

    i would rather have coffee for breakfast and save my calories for later in the day...

    i LOVE to snack at night, and used to feel guilty about it and stress...now i dont, because i have the calories.
  • AlsDonkBoxSquat
    AlsDonkBoxSquat Posts: 6,128 Member
    I agree, it really doesn't matter if you eat 18 meals in one day or 1 meal in one day. I generally eat one meal that goes from the time I decide to start eating (anywhere between 630 and 9 AM and lasts until I fall asleep). I do this because if I at any time get hungry I get hangry, and if I get hangry people die.
  • sunlover89
    sunlover89 Posts: 436 Member
    Yeah, I get that. But the guy I was talking to said I HAD to eat every three hours to burn fat! And that if I ate all my calories in one or two meals I would get fat. Silly billy..
  • MikeyD1280
    MikeyD1280 Posts: 5,257
    Our bodies are like a wood stove. If you try to put x amount of logs in the stove at one shot, it more than likely will not burn. If you start it with 3 small pieces instead of let's call "x" 9, you can get a fire going. Once the fire is going, if you put too much wood in the stove it will die out. This analogy IMO works with how we are designed as well. If you eat just enough each meal, the fire will still burn. If you load it all up in one meal, it will be to hard on our body and will not burn as fast and will eventually die down. (Anyone who is familiar with a wood burning stove would know what I mean).
    Obviously I know we are not wood stoves but only use it as an analogy. Seeing posts like this make me think of people saying after sprinting hard and sweating your *kitten* off, you know, the workouts that you have a hard time talking because it's so intense, would say that I know you are thirsty now, but you can drink water in 5 hours from now, it will do you just as good... no you need to do so right then and there. IMO you do have windows to eat or drink, just because you cannot feel the need for certain things-- such as the need for water/gatorade/whatever, after a crazy cardio session-- doesn't mean you are fueling properly.

    "Facts" such as any about how and when to eat are just science because what works for one doesn't necessarily work for someone else. To say that it is WRONG to do something a specific way is not a heads up, it's misinformed. There are hundreds of ways to get to the number 100, 1+99, 50+50, 10^2 and so on... same thing about this... I eat spread out and it has always done good for me, I am no bodybuilder, but I been in decent shape for over 15 years eating throughout the day more than just 3 meals...

    And just curious, why say it makes you sad when bodybuilders make claims when they are winning trophies?
  • vypeters
    vypeters Posts: 475 Member
    Yep.

    I'm an 'eat small amounts frequently' person because I'm a grazer (so effectively I'm just grazing my food instead of eating meals) and I love, love, love it. But I don't have any voodoo mystical illusions about its merits except that it keeps me satisfied and feeling good.

    Healthy foods, moderate quantities, distributed in a way that meets your needs. No need to make it more complicated.
  • psuLemon
    psuLemon Posts: 38,432 MFP Moderator
    Our bodies are like a wood stove. If you try to put x amount of logs in the stove at one shot, it more than likely will not burn. If you start it with 3 small pieces instead of let's call "x" 9, you can get a fire going. Once the fire is going, if you put too much wood in the stove it will die out. This analogy IMO works with how we are designed as well. If you eat just enough each meal, the fire will still burn. If you load it all up in one meal, it will be to hard on our body and will not burn as fast and will eventually die down. (Anyone who is familiar with a wood burning stove would know what I mean).
    Obviously I know we are not wood stoves but only use it as an analogy. Seeing posts like this make me think of people saying after sprinting hard and sweating your *kitten* off, you know, the workouts that you have a hard time talking because it's so intense, would say that I know you are thirsty now, but you can drink water in 5 hours from now, it will do you just as good... no you need to do so right then and there. IMO you do have windows to eat or drink, just because you cannot feel the need for certain things-- such as the need for water/gatorade/whatever, after a crazy cardio session-- doesn't mean you are fueling properly.

    "Facts" such as any about how and when to eat are just science because what works for one doesn't necessarily work for someone else. To say that it is WRONG to do something a specific way is not a heads up, it's misinformed. There are hundreds of ways to get to the number 100, 1+99, 50+50, 10^2 and so on... same thing about this... I eat spread out and it has always done good for me, I am no bodybuilder, but I been in decent shape for over 15 years eating throughout the day more than just 3 meals...

    And just curious, why say it makes you sad when bodybuilders make claims when they are winning trophies?

    Unfortunately, the evidence of eating within a specific window is anecdotal at best. While eating more frequent might improve satiety, the science shows that it won't increase weight or fat loss at all. And in many cases it doesn't show improvements in even 1rep max sets. So at this point, if it works for you great, but many would suggest IF is just as effective as eating meals throughout the day. I know for me, I much prefer to eat every few hours.