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"A calorie is a calorie" violates the second law of thermodynamics

ncbi.nlm.nih.gov

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Re: "A calorie is a calorie" violates the second law of thermodynamics

#41

Post by Udo »

colomon wrote: post #38
Udo wrote: post #27

Earlier quoted context omitted.

Exactly. I also believe it doesn't really matter, because the inefficiencies of converting sugars to body fat are pretty much irrelevant. Proteins may have a more significant inefficiency, but it's hard find food where they are the majority component. When people overeat grossly, those 5% won't make much of a difference. On my binge days, I consume upwards of 5000 kcal and it doesn't really matter if it's actually ju…

Huh? Just because one can binge so much that the difference is irrelevant hardly means that the difference isn't important in general. The study this cites early on suggests that a low-carbohydrate diet with N calories a day is roughly equivalent to a low-fat diet with only 70% of N calories a day. So a 2000 calorie-a-day low-carbohydrate diet is equivalent to a 1400 calorie-a-day low-fat diet. That result is huge .…

I allege that it indeed makes very little difference, except in cases where people indeed manage to eat only one category (most food is a mix, even when people claim to be on a diet).

As other people said, the results of this study are not new. We learned that in basic biochemistry when the metabolic pathways were discussed.

> So a 2000 calorie-a-day low-carbohydrate diet is equivalent to a 1400 calorie-a-day low-fat diet.

It is so not.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#42

Post by colomon »

run4yourlives wrote: post #12

"A calorie is a calorie" is good enough, however. People aren't fat because they are consuming 2500 calories from a Big Mac and Fries rather than 2500 calories from carrots. People are fat because they are consuming 6000 calories and burning off 1300. The message is simplistic, sure. For a large majority of overweight people though that's all that is required. Somewhere between reducing caloric intake and becoming fi…

Errr.... consuming 6000 calories and burning off only 1300 would cause you to gain more than a pound. That might be a daily intake for someone weighing 600 pounds, but it's hardly the situation for your run-of-the-mill fat person.

Putting it in practical, personal terms -- I was laid up for six weeks for medical reasons this winter, and my bad habits continued for the next six weeks as well. Over that period I gained about 18 pounds, one of the worst periods of weight gain in my life. Simple math (and ignoring the data presented in the article!) tells you I must have been eating about 5250 excess calories a week. Roughly speaking I was probably eating 23,000 calories a week when I should have been having 18,000.

Now suppose I had gained that weight on a low-fat diet. The study cited in the article suggests that if I had been on a low-carb diet instead, I wouldn't have gained any weight at all! That's a pretty significant result. (Of course, in practice I was on a "whatever" diet.)

For those of us living on the edge, trying to shave off 500 calories a day, the knowledge that not all calories are created equal is a Big Deal.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#43

Post by colomon »

Udo wrote: post #41
colomon wrote: post #38

Earlier quoted context omitted.

Huh? Just because one can binge so much that the difference is irrelevant hardly means that the difference isn't important in general. The study this cites early on suggests that a low-carbohydrate diet with N calories a day is roughly equivalent to a low-fat diet with only 70% of N calories a day. So a 2000 calorie-a-day low-carbohydrate diet is equivalent to a 1400 calorie-a-day low-fat diet. That result is huge .…

I allege that it indeed makes very little difference, except in cases where people indeed manage to eat only one category (most food is a mix, even when people claim to be on a diet). As other people said, the results of this study are not new. We learned that in basic biochemistry when the metabolic pathways were discussed. > So a 2000 calorie-a-day low-carbohydrate diet is equivalent to a 1400 calorie-a-day low-fat…

"A low carbohydrate group (LoCHO = 1800 kcal for men; 1500 kcal for women), a low fat group (LoFat, 1800 and 1500); a third group also consumed a low carbohydrate diet but an additional 300 kcalories were provided (LoCHO+300, 2100 and 1800). The order of average amount of weight lost was LoCHO = 23 lbs, LoCHO+300 = 20 lbs LoFat = 17 lbs." That's not quite the same math I used, but it seems to pretty strongly suggest that a LoCHO+600 group would have have lost 17 lbs, exactly the same as the LoFat group.

Perhaps there is some reason to doubt this study, but saying "It is so not" is hardly a rational rebuttal.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#45

Post by [deleted] »

ugh wrote: post #22
run4yourlives wrote: post #12

"A calorie is a calorie" is good enough, however. People aren't fat because they are consuming 2500 calories from a Big Mac and Fries rather than 2500 calories from carrots. People are fat because they are consuming 6000 calories and burning off 1300. The message is simplistic, sure. For a large majority of overweight people though that's all that is required. Somewhere between reducing caloric intake and becoming fi…

Simply counting calories will reduce your weight. I can pretty much confirm that now. Over the last eight months I tried to stay below 1900 calories per day and I have lost 17 kilo. As much as I wanted to, I did not manage to change my diet in any meaningful way, I’m just eating less. I didn’t even manage to keep up a regular sports routine. But my fallback – mercilessly tracking my weight and counting calories – sav…

[deleted]

Re: "A calorie is a calorie" violates the second law of thermodynamics

#46

Post by heyitsnick »

ugh wrote: post #22
run4yourlives wrote: post #12

"A calorie is a calorie" is good enough, however. People aren't fat because they are consuming 2500 calories from a Big Mac and Fries rather than 2500 calories from carrots. People are fat because they are consuming 6000 calories and burning off 1300. The message is simplistic, sure. For a large majority of overweight people though that's all that is required. Somewhere between reducing caloric intake and becoming fi…

Simply counting calories will reduce your weight. I can pretty much confirm that now. Over the last eight months I tried to stay below 1900 calories per day and I have lost 17 kilo. As much as I wanted to, I did not manage to change my diet in any meaningful way, I’m just eating less. I didn’t even manage to keep up a regular sports routine. But my fallback – mercilessly tracking my weight and counting calories – sav…

> Simply counting calories will reduce your weight. I can pretty much confirm that now. Over the last eight months I tried to stay below 1900 calories per day and I have lost 17 kilo.

And simply not counting calories will reduce your weight. I can pretty much confirm that now.

Over the last 3 months I have stopped counting or considering calories, eaten as much as I wanted, and I've lost nearly 20lbs. Nothing crazy, I've gone from an overweight 190lbs to much leaner 170lbs.

I roughly followed a slow-carb diet but broken it so many times I've lost count.

Individual data points are nice but they don't tell any story. Pretty much following any diet can be shown to have significant weight-loss, even those that appear to take opposite strategies.

This is in part due to underlying similarities (nearly all diets involve a reduction in sugars and HFCS, and generally practice monitoring your weight and motivational tips such as making rules explicit).

What this pub is trying to do is dispell some myths regarding the whole "low-carb diets can't work because of the law of thermodynamics!" rubbish.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#47

Post by hackermom »

This is entirely besides the point of the study and the article, but why are the Americans the only ones who, in terms of human energy intake/consumption, say calorie when it should be kilocalorie? Why do they insist on being one thousand times off? "It's easier"? From where does this come from, and why does the rest of the world insist on being accurate?

Re: "A calorie is a calorie" violates the second law of thermodynamics

#48

Post by daoudc »

dmarquis wrote: post #7
thirsteh wrote: post #2

I thought that "Richard Feinman" was just a misspelling of Richard Feynman, then I noticed the dates. That would be just like him to author something like this though.

Its a good first approximation so to a physicist it might as well be true.

Ouch. Yes, I clearly remembering being taught that Physics is approximation.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#49

Post by mhd »

keeptrying wrote: post #26
ugh wrote: post #22

Earlier quoted context omitted.

Simply counting calories will reduce your weight. I can pretty much confirm that now. Over the last eight months I tried to stay below 1900 calories per day and I have lost 17 kilo. As much as I wanted to, I did not manage to change my diet in any meaningful way, I’m just eating less. I didn’t even manage to keep up a regular sports routine. But my fallback – mercilessly tracking my weight and counting calories – sav…

If you simply cut out carbs you will lose a ton of fat. But yeah if you want to eat carbs and be healthy you have to basically count calories for the rest of your life.

Well, for a lot of people giving up bread and pasta is a lot harder than counting calories. Never mind the fact that there's an awful lot of "bro science" in the no/low/slow-carb crowd.

Re: "A calorie is a calorie" violates the second law of thermodynamics

#50

Post by ugh »

regularfry wrote: post #35
ugh wrote: post #22

Earlier quoted context omitted.

Simply counting calories will reduce your weight. I can pretty much confirm that now. Over the last eight months I tried to stay below 1900 calories per day and I have lost 17 kilo. As much as I wanted to, I did not manage to change my diet in any meaningful way, I’m just eating less. I didn’t even manage to keep up a regular sports routine. But my fallback – mercilessly tracking my weight and counting calories – sav…

Surely this is just an application of the maxim "Anything measured improves," rather than anything specific to weight control?

I do believe that measuring is vital but I don’t believe that it is enough (17 kilo are not random weight loss). There must still be an underlying cause. I attribute that to my calorie counting.
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