3500 calories = 1 pound?

AwesomeGuy37
AwesomeGuy37 Posts: 436 Member
in Getting Started
I know this seems to be the rule of thumb when losing weight counting calories, but....

Where did this come from exactly? By exactly, I mean exactly.. Who said it, why was it adopted, and how is is calculated scientifically?

Everywhere I look it seems to be an assumption without ever a source. I've just come to assume it is a rough guess of how many calories are in 1 pound of average weight lost since 1 pound of pure fat would be closer to 4086 calories. (9cal*454grams)

Does anyone know the facts?

Replies

  • _Terrapin_
    _Terrapin_ Posts: 4,301 Member
    I saw it on a billboard....source was yahoo answers and a Korean actor was the spokesman; IDK, figures lie, and our figures matter, so not sure. But good luck on the quest.
  • TapouTFTW
    TapouTFTW Posts: 72
    Lets start with this...
    http://getwhealthy.wordpress.com/2013/02/11/calorie-counting-worth-it-or-totally-bogus/

    Now here is the really important stuff...
    http://www.fitwatch.com/weight-loss/3500-calories-to-lose-a-pound-is-this-formula-all-wrong-237.html

    http://www.fitday.com/fitness-articles/fitness/weight-loss/weight-loss-myth-the-more-calories-you-cut-the-more-weight-youall-lose.html
  • NapsAndNachos
    NapsAndNachos Posts: 80
    The adipose tissue isn't 100% lipids. To be fair, the caloric intake and usage is always going to have to be an approximation, so to say that to lose a pound of fat you need to expend 3500 kcal is close enough. I was always told that one kilo of fat is 7000 kcal, and one kilo is 2.2 pounds. I just let it go and didn't let it bother me :-) But I hope someone can give you a better answer.
  • hill8570
    hill8570 Posts: 1,466 Member
    IIRC, a human fat cell is on the order of 87% lipid, so a pound of body fat cells contains a bit over 3500 calories of "fat".

    Like most things, it's an estimate. As is your base metabolic burn, your burn through exercise, and the number of calories in your food. You use all those estimates to get a ballpark guess as to what you need to do to lose weight, and then adjust things as the weeks go by.
  • AwesomeGuy37
    AwesomeGuy37 Posts: 436 Member
    I saw it on a billboard....source was yahoo answers and a Korean actor was the spokesman; IDK, figures lie, and our figures matter, so not sure. But good luck on the quest.

    Thanks.
    IIRC, a human fat cell is on the order of 87% lipid, so a pound of body fat cells contains a bit over 3500 calories of "fat".

    Like most things, it's an estimate. As is your base metabolic burn, your burn through exercise, and the number of calories in your food. You use all those estimates to get a ballpark guess as to what you need to do to lose weight, and then adjust things as the weeks go by.

    The adipose tissue isn't 100% lipids. To be fair, the caloric intake and usage is always going to have to be an approximation, so to say that to lose a pound of fat you need to expend 3500 kcal is close enough. I was always told that one kilo of fat is 7000 kcal, and one kilo is 2.2 pounds. I just let it go and didn't let it bother me :-) But I hope someone can give you a better answer.

    That seems to make sense with the adipose tissue explanation for the 3500. Still if we go by this then we must assume weight lost is adipose tissue? When someone loses more than 2 pounds we assume it is muscle or water weight, while if they gain weight we assume they retained water weight? I get lost there.
    I don't disagree with the ballpark figures working for weight loss, but it bugs me not knowing the science behind it.
    Lets start with this...
    http://getwhealthy.wordpress.com/2013/02/11/calorie-counting-worth-it-or-totally-bogus/

    Now here is the really important stuff...
    http://www.fitwatch.com/weight-loss/3500-calories-to-lose-a-pound-is-this-formula-all-wrong-237.html

    http://www.fitday.com/fitness-articles/fitness/weight-loss/weight-loss-myth-the-more-calories-you-cut-the-more-weight-youall-lose.html

    Interesting read, but I don't think the information there debunks calorie counting. I am really skeptical of the guy selling his program. I'll have to continue researching. Thanks for the info.
  • NapsAndNachos
    NapsAndNachos Posts: 80

    That seems to make sense with the adipose tissue explanation for the 3500. Still if we go by this then we must assume weight lost is adipose tissue? When someone loses more than 2 pounds we assume it is muscle or water weight, while if they gain weight we assume they retained water weight? I get lost there.
    I don't disagree with the ballpark figures working for weight loss, but it bugs me not knowing the science behind it.

    I don't quite follow what you're saying. Weight loss isn't linear. The caloric in and out starts to look about right when you follow it for several weeks and months. Also, I think that there are some extreme conditions where either not all food is digested (the energy input is lower than we assume) or our expenditure becomes much lower/higher for specific reasons. It is still never really linear. People might stall for a long time, even in larger caloric deficit. I've read that the explanation for that is that the fat cells are filled with water, but that the fat has still been lost.

    In any case, counting calories for both input and expenditure are always going to be rough estimates and will only look about right after you are able to look past data. Or rather, you'll know the truth about your expenditure after looking at past data. Unfortunately we can't even base many future decisions on that, since our bodies are constantly changing and they certainly are, if your body composition changes radically during a diet. I still think that calorie counting is "close enough" to know how much you've eaten, especially when eating this and that and not in regular intervals.
  • AwesomeGuy37
    AwesomeGuy37 Posts: 436 Member

    That seems to make sense with the adipose tissue explanation for the 3500. Still if we go by this then we must assume weight lost is adipose tissue? When someone loses more than 2 pounds we assume it is muscle or water weight, while if they gain weight we assume they retained water weight? I get lost there.
    I don't disagree with the ballpark figures working for weight loss, but it bugs me not knowing the science behind it.

    I don't quite follow what you're saying. Weight loss isn't linear. The caloric in and out starts to look about right when you follow it for several weeks and months. Also, I think that there are some extreme conditions where either not all food is digested (the energy input is lower than we assume) or our expenditure becomes much lower/higher for specific reasons. It is still never really linear. People might stall for a long time, even in larger caloric deficit. I've read that the explanation for that is that the fat cells are filled with water, but that the fat has still been lost.

    In any case, counting calories for both input and expenditure are always going to be rough estimates and will only look about right after you are able to look past data. Or rather, you'll know the truth about your expenditure after looking at past data. Unfortunately we can't even base many future decisions on that, since our bodies are constantly changing and they certainly are, if your body composition changes radically during a diet. I still think that calorie counting is "close enough" to know how much you've eaten, especially when eating this and that and not in regular intervals.

    I was asking questions. I just mean I don't think it is linear. I agree. This 3500 coming from the dry adipose tissue would account for the missing fat calories in the calculation, but we don't lose pure adipose tissue. We actually lose a % of muscle, body fluids, and other stuff that isn't factored in. Still I want to find the study or research done to find this 3500 number.
  • ChrisM8971
    ChrisM8971 Posts: 1,067 Member

    That seems to make sense with the adipose tissue explanation for the 3500. Still if we go by this then we must assume weight lost is adipose tissue? When someone loses more than 2 pounds we assume it is muscle or water weight, while if they gain weight we assume they retained water weight? I get lost there.
    I don't disagree with the ballpark figures working for weight loss, but it bugs me not knowing the science behind it.

    I don't quite follow what you're saying. Weight loss isn't linear. The caloric in and out starts to look about right when you follow it for several weeks and months. Also, I think that there are some extreme conditions where either not all food is digested (the energy input is lower than we assume) or our expenditure becomes much lower/higher for specific reasons. It is still never really linear. People might stall for a long time, even in larger caloric deficit. I've read that the explanation for that is that the fat cells are filled with water, but that the fat has still been lost.

    In any case, counting calories for both input and expenditure are always going to be rough estimates and will only look about right after you are able to look past data. Or rather, you'll know the truth about your expenditure after looking at past data. Unfortunately we can't even base many future decisions on that, since our bodies are constantly changing and they certainly are, if your body composition changes radically during a diet. I still think that calorie counting is "close enough" to know how much you've eaten, especially when eating this and that and not in regular intervals.

    I was asking questions. I just mean I don't think it is linear. I agree. This 3500 coming from the dry adipose tissue would account for the missing fat calories in the calculation, but we don't lose pure adipose tissue. We actually lose a % of muscle, body fluids, and other stuff that isn't factored in. Still I want to find the study or research done to find this 3500 number.

    When I did some research at the start of my weight loss I read an article that put the calories around 3545 per lb of fat based on % lipids within the body fat, with 3500 being the nearest round number. You are correct in the fact that losing weight will involve losing muscle and water weight, which is probably why weekly losses vary (how often do you hear that weight loss is not linear)

    But if you are looking at this from a weight loss point of view I don't think you will find any research that says "a 3500 deficit will result in you losing 1 lb" The 3500 here is a number which is designed to put you in approximately the right ball park to start with.

    At the end of the day we can't really tell "exactly" how many calories per day we are eating due to accuracy levels of measuring devices and the allowable tolerances for food labels etc
  • NapsAndNachos
    NapsAndNachos Posts: 80

    I was asking questions. I just mean I don't think it is linear. I agree. This 3500 coming from the dry adipose tissue would account for the missing fat calories in the calculation, but we don't lose pure adipose tissue. We actually lose a % of muscle, body fluids, and other stuff that isn't factored in. Still I want to find the study or research done to find this 3500 number.

    That's right. We never do lose just fat, so weight loss != fat loss. Most of us want to lose fat, even when we say that we want to lose weight. So I think it's then just become this saying that you should expend 3500 kcal to lose a pound. In reality, it's much more complex than that.

    I'm sure there are studies of adipose tissue composition, which would lead to the approximation of 3500 kcal for a pound of fat. I'm just too lazy to search for it, but then again, I'm not the one asking for it ;-)
  • yarwell
    yarwell Posts: 10,477 Member
    Where did this come from exactly? By exactly, I mean exactly.. Who said it, why was it adopted, and how is is calculated scientifically?

    http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3859816/ references http://ajcn.nutrition.org/content/6/5/542.long which I beleive is the "origin" of 3500 in the 1950s.

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