I know low-carb has been done to death around here, but I had one more question about the physiology of low-carb diets. It seems like the theory behind them would allow quite a lot of calorie consumption without weight gain, as long as you didn’t eat many carbohydrates, because you keep insulin low and thus fat-burning high.
So let’s say you need 1000 cals to maintain your body weight. As far as the theory goes, if you eat 1000 cals of a high carb diet, you’d use maybe 800 for your cells, and the other 200 would be driven to fat storage by the high insulin levels. So then your body would perceive a 200 cal energy deficit and that, in combination with the drop in insulin, would make you hungry. If you could avoid eating any more, your body would burn a combo of stored fat + muscle to make up for that 200 cals, or it would slow down further to make your daily metabolic needs only 800 cals.
If you ate 1000 cals on a low-carb diet, it would all go to tissues where it’s needed and you’ll feel satiated and happy. Similarly, if you only ate 800 cals on a low-carb diet, the body could easily make up the deficit by burning fat, since insulin is low, and you’d lose weight.
Okay, so that is what the theory behind low-carbing says. Here’s where my question comes in. What if you only need 1000 cals but eat 1500 cals on a low-carb diet? That extra 500 cals has to go somewhere, right? Why wouldn’t it be stored as fat? Does the body’s metabolism just increase in order to burn that extra 500 cals?