The 500 calorie deficit myth

Hi All -

http://charlotteord.blogspot.co.uk/2013/03/the-500-calorie-deficit-myth.html


I saw the below blog and became very disencouraged.. can you all shed some light on your experiences to keep me going.. i dont want to believe this is true?




The 500 calorie deficit myth
A few days ago I wrote about why the widely accepted belief that a pound of fat equals 3500 calories is actually a real estimate, and consequently flaws 99% of modern day diet protocols, given that they are based steadfastedly on this belief and calculated down to the last calorie.

Today I'm going to expand on that and explain why, subsequently, the notion that if you create a daily 500 calorie deficit (either through reduced calorie intake or increased energy expenditure through exercise) you'll lose a pound of fat a week, is also incorrect, and not only that, but will actually set you up for GAINING weight long term.

Firstly, the 500kcal a day deficit is based on the assumption that 3500kcals equals 1lb of fat, which we've already established is a dodgy formula to say the least.

The 500kcal deficit myth suggests that weight loss is a linear affair and that, if you cut calories by x amount each day, you will experience x weight loss, in a linear fashion. Anyone who has ever been on any kind of calorie restricting diet will know already that this is absolutely not true. And yet we blindly choose to follow the protocol over and over again, assuming that for some reason, our bodies will respond differently this time.

The theory suggests that, if I were to cut my calories by 500kcals per day, say from 2000 to 1500kcal (more than what most modern day diets recommend), I would lose 1lb (of pure fat) per week. If I did that for 1 year I would have lost 52lbs, which is nearly 4 stone. I can categorically tell you that if I ate 1500kcals per day for the next year I would not end up weighing in at around 5 stone. So why do we still believe that this is the way to lose fat?

The reason why fat loss isn't linear is that there is more going on within the body than a simple calories in vs. calories out exchange. The body is exceptionally good at self preservation and, when faced with a large deficit, will shut down any non essential functions in order to protect itself. For example, loss of menstruation occurs in women (amenorrhea) because reproduction is non-essential. In fact everything slows down.

The body also recognises that lean muscle tissue requires 3 times as many calories as fat just to maintain itself, and so starts to utilise lean tissue as fuel instead, which has a knock on effect on basal metabolic rate (the amount of calories you burn at complete rest). This is obviously counterproductive for fat loss.

How the 500kcal deficit myth is even still around is puzzling. One of the most important studies ever conducted for obesity categorically proved it does not work.

In 1944, in the midst of World War II, an American doctor, Ancel Keys, set out to find out what happened to men who faced prolonged rationing, and subsequently starvation, during the war. The study was intended to determine the most effective method of refeeding men who had been on very low calorie diets, but turned into one of the most important studies for weight management ever.

36 healthy men took part in the study, which began with a 12 week control period to determine each man's daily calorie intake requirement to maintain their weight whilst doing around 45-60mins walking a day (approx 3120).

Following this the men took part in a 12 week starvation period, where they ate a diet of around 1500kcals a day (note they still ate 1500kcals per day - more than most modern day diets recommend!) with the same amount of walking.

The men were then split into 4 groups (each consuming a different refeeding strategy to test various strategies) for 12 week, known as the restricted rehabilitation phase.

And finally they completed an 8 week unrestricted phase where they could eat what they liked.

What Keys found was incredible.

The men, who were required to keep diaries throughout the study, reported extreme depression, self-harm (possibly as a distraction from hunger pain), muscle wastage, loss of libido, irritability, dizziness, loss of motivation, reduced coordination and hair loss. They became obsessed with food and anything to do with it, displaying characteristics not dissimilar to those of an anorexic. In fact, they lost interest in anything other than food (such is the human drive to overcome hunger).

They found themselves having to resist overwhelming urges to binge, and the couple who did succumb to the urge to do so reported feeling intense feelings of guilt and shame.

Weight wise, the men lost an average of 37lbs during the starvation period (1.5lbs per week), less than half of what they should have lost if the 500kcal a day deficit theory actually worked. Indeed, in order to keep the men losing weight throughout the starvation period, Keys had to keep on reducing their calorie intake week after week, indicating that the less you eat, the less you must continue to eat in order to keep on losing weight. Amazingly, one man actually recorded a weight GAIN in the final week of the starvation period. The body really will do anything it can to avoid the effects of starvation and dieting!

Equally interesting was what happened to the men once they entered the unrestricted phase of the experiment.

They overrate.

They binged.

They would eat over 10,000 calories a day.

Even when they were full to bursting they carried on eating.

They all gained all the weight back that they had lost and an average of 10% MORE than the weight they started at.

They started to 'feel fat' and report negative body images despite having never thought that way before.

Sound familiar?

What happened in the Minnesota Starvation Experiment was exactly what happens when people follow calorie restricted diets.

They eat less, get really hungry, the body slows metabolism down and increases the desire to eat, willpower caves in, they overeat, gain weight, and the whole cycle starts over again.

There's a lot more to be said on this but for now the take home advice is this:

When you go on a calorie restricted diet and you end up, weeks or months later, weighing more than you did initially, this is not you defying science. Nor is it you being weak-willed. When it comes to weight loss, your body is trying to look out for you, and will try and keep you alive as best it can. If you deny it calories it will shut everything down and get rid of the one thing that keeps you lean, your muscle tissue.

Counting calories does not work, and we need to understand that before we really commit to what will (more on that to follow!).

References

Harcombe, Z (2010) The Obesity Epidemic. Comlumbus Publishing Ltd.

Tucker, Todd (2006). The Great Starvation Experiment: Ancel Keys and the Men Who Starved for Science. New York: Free Press.
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Replies

  • sloth3toes
    sloth3toes Posts: 2,212 Member
    TL;DR but want in.
  • _Zardoz_
    _Zardoz_ Posts: 3,987 Member
    The men in this experiment were already at a healthy weight which is why the results don't really work when applied to over weight or obese people
  • The men in this experiment were already at a healthy weight which is why the results don't really work when applied to over weight or obese people

    im not sure if i have understood correctly but if i am at a healthy weight but am just trying to loose a stuborn 5kg then does that mean that 500 deficit wont work for me and its a matter of eating healthier foods??
  • CatBird128
    CatBird128 Posts: 14 Member
    I think the big lesson from ALL the studies is that no one can really know what any one person's metabolism is doing. They can look at overall average numbers from large groups of people to try to predict the outcome - but when it's you on your own diet/fitness plan, you don't know whether you're exactly average, or leaning towards one end or the other of the spectrum - ESPECIALLY when you consider that your own metabolism will change as your body adjusts to the diet, so even that isn't ever 100% known at any time either.

    The only thing you can do is choose a healthy diet/fitness plan that works for you, and stick with it long enough to ascertain whether it is working, and then make adjustments in physical activity and calories to correct your metabolism, which will change as your diet does.
  • albayin
    albayin Posts: 2,524 Member
    I think the big lesson from ALL the studies is that no one can really know what any one person's metabolism is doing. They can look at overall average numbers from large groups of people to try to predict the outcome - but when it's you on your own diet/fitness plan, you don't know whether you're exactly average, or leaning towards one end or the other of the spectrum - ESPECIALLY when you consider that your own metabolism will change as your body adjusts to the diet, so even that isn't ever 100% known at any time either.

    The only thing you can do is choose a healthy diet/fitness plan that works for you, and stick with it long enough to ascertain whether it is working, and then make adjustments in physical activity and calories to correct your metabolism, which will change as your diet does.

    I like this post. :)

    Having said that, I become to believe there are more than food in/energy out theory, besides the metabolism, our hormones, genes all play big part in the show...they are even harder to track. :( I wish it was as clean as "calorie in, calorie out"....
  • I think the big lesson from ALL the studies is that no one can really know what any one person's metabolism is doing. They can look at overall average numbers from large groups of people to try to predict the outcome - but when it's you on your own diet/fitness plan, you don't know whether you're exactly average, or leaning towards one end or the other of the spectrum - ESPECIALLY when you consider that your own metabolism will change as your body adjusts to the diet, so even that isn't ever 100% known at any time either.

    The only thing you can do is choose a healthy diet/fitness plan that works for you, and stick with it long enough to ascertain whether it is working, and then make adjustments in physical activity and calories to correct your metabolism, which will change as your diet does.

    Thanks for the advise! im going to try cleaning up my calories abit as in the nutrition im getting. i always have high sugar levels when the dr takes my bloods and really need to control that. i think that can play a big part in stopping me from loosing as the first thing the body burns is glucose. it also effects my hormones massivley!
  • cafeaulait7
    cafeaulait7 Posts: 2,459 Member
    The men in this experiment were already at a healthy weight which is why the results don't really work when applied to over weight or obese people

    im not sure if i have understood correctly but if i am at a healthy weight but am just trying to loose a stuborn 5kg then does that mean that 500 deficit wont work for me and its a matter of eating healthier foods??

    If a 500 calorie deficit is above your BMR and you get enough protein (and fats and carbs, but particulary protein) AND do some form of weight-bearing exercise, you should be totally fine. Well, if your goal is healthy. Trying to become underweight is a different story in terms of what goes on.
  • AllonsYtotheTardis
    AllonsYtotheTardis Posts: 16,947 Member
    I ate at a 500 cal deficit and lost 50 lbs in my first 52 weeks.

    Stop worrying about what a BLOG is saying. Worry about what you're doing, instead.
  • rileysowner
    rileysowner Posts: 8,329 Member
    Sounds like a misreading of things to me. Counting calories does work, many people here who not only took off the weight, but keep it off are a testament to this. Notably there is a decided lack of reference cited.
  • kgeyser
    kgeyser Posts: 22,505 Member
    I got to the second line and stopped. Who is this blogger and why should I care about their opinion on anything? Anyone can make a blog and write a post. I have my food diary and a scale showing that a 500 calorie deficit is clearly working. I'm content to not mess with a good thing.
  • The men in this experiment were already at a healthy weight which is why the results don't really work when applied to over weight or obese people

    im not sure if i have understood correctly but if i am at a healthy weight but am just trying to loose a stuborn 5kg then does that mean that 500 deficit wont work for me and its a matter of eating healthier foods??

    If a 500 calorie deficit is above your BMR and you get enough protein (and fats and carbs, but particulary protein) AND do some form of weight-bearing exercise, you should be totally fine. Well, if your goal is healthy. Trying to become underweight is a different story in terms of what goes on.

    thanks - so i may be doing this wrong in that case.. i do strength training 3 time a week my weight is 62kg im 170 cm my BMR is 1400 and TDEE is 1800 and i aim to eat 1200 calories a day... should i up my calories my 100?
  • QuietBloom
    QuietBloom Posts: 5,413 Member
    None of this was particularly earth shattering. We have long known that the body doesn't lose 100% fat while in a calorie deficit, so that is just misleading. The Minnesota Starvation study was done on healthy weight subjects. It's interesting, but doesn't prove anything except that prolonged extreme calorie deficit is bad. We also already know that. This is why MFP recommends a REASONABLE calorie deficit and calorie counting (which DOES, in fact, work). 500 calories may not be a reasonable deficit for many people, but it may be for others. It depends on how much you have to lose in the first place. It's all about maximizing fat loss and minimizing muscle loss by eating your macros and exercising. And yes, for each individual, it IS calories in, calories out. If you eat less than you burn you will lose weight, and vise versa. This article just perpetuates some myths while repeating half truths.
  • QuietBloom
    QuietBloom Posts: 5,413 Member
    I think the big lesson from ALL the studies is that no one can really know what any one person's metabolism is doing. They can look at overall average numbers from large groups of people to try to predict the outcome - but when it's you on your own diet/fitness plan, you don't know whether you're exactly average, or leaning towards one end or the other of the spectrum - ESPECIALLY when you consider that your own metabolism will change as your body adjusts to the diet, so even that isn't ever 100% known at any time either.

    The only thing you can do is choose a healthy diet/fitness plan that works for you, and stick with it long enough to ascertain whether it is working, and then make adjustments in physical activity and calories to correct your metabolism, which will change as your diet does.

    Thanks for the advise! im going to try cleaning up my calories abit as in the nutrition im getting. i always have high sugar levels when the dr takes my bloods and really need to control that. i think that can play a big part in stopping me from loosing as the first thing the body burns is glucose. it also effects my hormones massivley!

    Your metabolism does not change as you lose weight, except that a smaller body requires fewer calories at rest than a larger one. That is why it is important to keep updating your weight in your profile, so MFP can adjust.
  • Mr_Bad_Example
    Mr_Bad_Example Posts: 2,403 Member
    It's a crap article written by a 'fitness coach' who, if you go to her main page, wants you to download and buy e-books that probably tell you she knows better than what's out there and that her way is the best. Maintaining a caloric deficit will result in weight loss - I and many others are proof of that.

    Now, go forth and kick some *kitten* OP.
  • QuietBloom
    QuietBloom Posts: 5,413 Member
    The men in this experiment were already at a healthy weight which is why the results don't really work when applied to over weight or obese people

    im not sure if i have understood correctly but if i am at a healthy weight but am just trying to loose a stuborn 5kg then does that mean that 500 deficit wont work for me and its a matter of eating healthier foods??

    If a 500 calorie deficit is above your BMR and you get enough protein (and fats and carbs, but particulary protein) AND do some form of weight-bearing exercise, you should be totally fine. Well, if your goal is healthy. Trying to become underweight is a different story in terms of what goes on.

    thanks - so i may be doing this wrong in that case.. i do strength training 3 time a week my weight is 62kg im 170 cm my BMR is 1400 and TDEE is 1800 and i aim to eat 1200 calories a day... should i up my calories my 100?

    If you only have a few lbs to lose, you should aim to lose 0.5 lbs per week or less. I would not eat less than your BMR.
  • prattiger65
    prattiger65 Posts: 1,657 Member
    IN
  • stumblinthrulife
    stumblinthrulife Posts: 2,558 Member
    <Looks at page of waffle>
    <Looks at year of consistent 1lb per week weight loss>
    <Looks at year of consistent 500 Calorie daily deficit>
    <Dismisses article offhand>

    Look, truth is that Calorie counting is an estimate, yes. And there are other factors that have an impact, yes. But ultimately Calories in vs. Calories out are such a large part of it that you can get everything else wrong, but the Calorie equation right, and still lose weight.

    So focus on getting Calories right first, and count everything else as secondary.
  • acogg
    acogg Posts: 1,870 Member
    "Counting calories does not work, and we need to understand that before we really commit to what will (more on that to follow!). "

    Yes, the world waits with bated breath for the new break through! Could it involve some new product or book?
  • SilviCor
    SilviCor Posts: 110 Member
    bump
  • moontyrant
    moontyrant Posts: 160 Member
    *sigh*
    If anyone undereats to the point of starvation, they are going to experience negative consequences like self-harming thoughts, binging, intense guilt, depression, etc. If you are at a healthy weight, cut your calories by 25% for purposes outside intentional weightloss, then allow yourself to eat whatever after an arbitrary amount of time, you will gain weight.

    However. If you cut your calories by a reasonable amount, maintain a healthy mindset and keep a change in diet for the rest of your life (a lifestyle change) you will lose weight and keep it off. Fad dieters regain weight because they eat 600 calories a day for four weeks, achieve a dress size, then go back to eating 4000 calories of fried chicken and corn dogs.

    In before "where's your studies," in before "the internet says," in before "meal timing/source of calories is irrelevant/starvation mode."
  • thanks everyone! this has been helpful. i think i have attempted to lose Kgs faster then needed and will up my calories to a healthier amount.

    im one of those people who ask the stupid questions LOL but if i dont ask i wont learn. so thanks for contributing with this.
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    When you go on a calorie restricted diet and you end up, weeks or months later, weighing more than you did initially, this is not you defying science.

    Nonsense.
    When it comes to weight loss, your body is trying to look out for you, and will try and keep you alive as best it can. If you deny it calories it will shut everything down and get rid of the one thing that keeps you lean, your muscle tissue.

    That comment is completely off the rails. The idea that your body will get rid of muscle that it DOES need to keep fat that it DOESN'T need is not supported by either common sense or science.

    And, specifically regarding the OP, it is not a statement supported by the very study the article is talking about.

    ...

    tl;dr The original study is solid, but the article writer is either misrepresenting or misunderstanding what the study actually showed.
  • ILiftHeavyAcrylics
    ILiftHeavyAcrylics Posts: 27,732 Member
    The men in Ancel Keys' study ate at a 50% deficit (I've recently been doing a bit of research involving that study). That's much larger than what is generally recommended and for good reason. The men in that study were eating at 3 times the recommended 500 calorie deficit.

    Personally and anecdotally I can tell you that I do better with a small deficit. But for most of my weight loss, when I had more to lose, I lost a pound per week without negative side effects. I've been in maintenance for over a year.
  • WalkingAlong
    WalkingAlong Posts: 4,926 Member
    I got to the second sentence. Reading a manifesto from some random blogger is one thing, but I'm not suffering through bad grammar to do so.
  • moontyrant
    moontyrant Posts: 160 Member
    "Counting calories does not work, and we need to understand that before we really commit to what will (more on that to follow!). "

    Yes, the world waits with bated breath for the new break through! Could it involve some new product or book?

    I always find it fascinating that a habit that costs literally nothing is so often "ineffective" but expensive miracle potions and spells are fool proof. I like tracking. I like being able to see how much I have been eating, how much is a reasonable amount for me to eat, and when to stop. I would rather track my cereal and weigh my cream cheese than chug warm syrup water any day.
  • toddis
    toddis Posts: 941 Member
    At the risk of ad hominem, the author's own reply to her article:
    "Thanks for your comments everyone, but take a look around. The population has never eaten so little and yet been so stricken by obesity-related disease. Sure, if you dramatically change your macronutrient and general food quality intake as a result of counting calories, then you will have success. But sadly most calorie counters fall foul of the enormous marketing machine that is the 'low calorie' food industry, and subsequently end up living on high sugar, high sweetener, nutrientless processed rubbish in order to get as much (sweet/refined) bang for their calorie quota buck as possible. These are the exact foods which equate to toxins in the body and which trigger insulin release and subsequent fat storage."

    Cuckoo.
  • ILiftHeavyAcrylics
    ILiftHeavyAcrylics Posts: 27,732 Member
    At the risk of ad hominem, the author's own reply to her article:
    "Thanks for your comments everyone, but take a look around. The population has never eaten so little and yet been so stricken by obesity-related disease. Sure, if you dramatically change your macronutrient and general food quality intake as a result of counting calories, then you will have success. But sadly most calorie counters fall foul of the enormous marketing machine that is the 'low calorie' food industry, and subsequently end up living on high sugar, high sweetener, nutrientless processed rubbish in order to get as much (sweet/refined) bang for their calorie quota buck as possible. These are the exact foods which equate to toxins in the body and which trigger insulin release and subsequent fat storage."

    Cuckoo.

    Oh. Ok then. :indifferent:
  • TribeHokie
    TribeHokie Posts: 711 Member
    The factual information that was presented is correct for the most part, but the blogger's conclusion is crap. It is true that eating at a deficit will not cause you to just lose fat, you will also lose lean muscle. This is why it is important to do strength training while trying to lose weight: so you do not have a massive hit to your ultimate bmr and muscle composition. It is also true that weight loss is not linear and you can't expect to lose on a schedule. This is due to many other factors, though, like water retention, hormonal changes, etc. As others have said, the Minnesota study was done with men who were already at a healthy weight, not obese or overweight, which is why they experienced such negative effects and massive bounce-backs after the deficit period was over. The hundreds of thousands of people who have started heavy and lost until they were at a healthy weight and then kept it off should prove to you that it is not inevitable that your body will "fight" you and make you gain back anything you lose. Keep doing what you're doing, you'll be fine.
  • vagabondgoddess
    vagabondgoddess Posts: 38 Member
    That's ridiculous. I'm not saying the studies are wrong. But the truth is you have to eat less calories than you are burning. That is fact. If it wasn't true then nobody on here would lose any weight.
  • Mr_Knight
    Mr_Knight Posts: 9,532 Member
    The population has never eaten so little...

    I'm sorry, no professional can be that out of touch. The article author is flat out lying, as we know for certain that Americans have never in history been eating more than they do today.