We've all heard the statistic that you need to burn about 3500 calories over maintenance to burn off a pound of fat. Is this accurate? It doesn't seem to make sense at goal weight. I mean over one year, a 100 surplus equals ten pounds.

Hypothetical situation: You have two twins who have the same BMR, do the same activities, etc. such that they burn the exact same number of calories. They eat the exact same food, except one of them drinks a 200 calorie soda in the morning. Will one be 20 pounds heavier than the other in a year?

We've all heard the statistic that you need to burn about 3500 calories over maintenance to burn off a pound of fat. Is this accurate? It doesn't seem to make sense at goal weight. I mean over one year, a 100 surplus equals ten pounds.

Hypothetical situation: You have two twins who have the same BMR, do the same activities, etc. such that they burn the exact same number of calories. They eat the exact same food, except one of them drinks a 200 calorie soda in the morning. Will one be 20 pounds heavier than the other in a year?

The answer is probably not. And it isn't because 1 pound of fat is not 3500 calories - that is very accurate. The issue that, based on your habits, your body is constantly striving for homeostasis. Your diurnal cycle shoots for this - you go through phases of anabolism (building tissue / storing fat) and catabolism (losing muscle / burning fat). Weight training and nutrition help sway those cycles so your anabolism is mainly tissue growth and your catabolism is mainly fat burning ... and the net result is a change.

If you constantly do the same thing, however, you will eventually stop seeing the results ... again, due to homeostasis. If you drop calories to 2000 and keep them there, eventually 2000 calories will be what your body maintains at. This is why people who over-analyze programs like BFL and try to count calories often fail ... because BFL was never meant to be a fixed-calorie program, it was meant to zig-zag your calories automatically because a portion of potato is not the same as a portion of apple. Zig-zagging calories is the single most effective method for fat loss because it does not allow homeostasis to take effect - you manipulate your calories so while the AVERAGE might be 2000, you're really taking in 2200 one day and 1800 the next, etc.

In the case of the twin drinking soda pop, the 200 calorie surplus would result in fat storage, that is for sure. But at some point, the metabolism of that twin would probably increase a bit to match the 200 calorie intake and then the fat gains would level off. This isn't necessary good because at that point they would be heavier with more fat.

The reason why most Americans continue to gain weight is not really a calorie question, in my opinion, it's more an insulin resistance question. First, the tons of carbs they load on come from sporadic sources, so they are zig-zagging calories - in other words, they aren't eating EXACTLY 3000 calories per day, but rather going all over with 3000 one day and 4000 etc - zig-zagging in the WRONG DIRECTION. Second, the overload of carbohydrates creates an influx of insulin and this creates insulin resistance and can lead to diabetes. This disease defies energy intake logic because your body's ability to store and release fat becomes skewed and you are able to gain because the normal signals to release fat (i.e. part of the machinery for homeostasis) is out of whack.

Any way, this is the issue. People focus so much on calories and it IS calories in and out, but you have to realize the equation is constantly changing. You are NOT at a "break even metabolism" of, say, 3000 so 2500 is the magic number. Just changing to 2500 may lower your metabolic rate from 3000 to 2800. Or, you might be able to eat 3000 but shift your calories to mostly lean proteins and healthy fats, and the thermic effect of the proteins could raise your metabolism to 3200 and you would start to lose weight. It's STILL calories in and out, but the equation changes with the inputs.

This is why splitting hairs on calories is such a dead-end. I count calories as a baseine and adjsut but realize there is no magic number and should be always ready to adapt. I also don't sweat over 100 calories here or there because I know there is no way anyone can track their foods to within 20% of actual calories - there is that margin of error built into food labels, and more error is introduced when people eyeball portion sizes and think they know the ounces of a piece of food, etc.

Heck, so many people buy 10% fat tuna and then don't even realize it becomes 30% fat during mating season that this small anomally itself can throw it all out of whack.

Whew ... fun stuff, no?

Jeremy

Hypothetical situation: You have two twins who have the same BMR, do the same activities, etc. such that they burn the exact same number of calories. They eat the exact same food, except one of them drinks a 200 calorie soda in the morning. Will one be 20 pounds heavier than the other in a year?

It all depends. Are they conjoined twins? And if they are, where are they attached?