Do all calories eaten in excess turn into body fat? Well, we can be sure that eating more fat and carbohydrate calories than our body can burn for energy, the extra calories of which will be stored as body fat. Then what about protein calories? Aren't all calories the same? Well, most people think so. However, the truth is controversial. At least, theoretically.

Since I can't find any research papers to confirm that extra protein calories ingested will not be stored as body fat, there is this theory that seems to support the idea. The lack of research to test this theory probably arises from the concern that subjects under clinical test may be under health risks as they must be put under a strict diet eliminating fats and carbohydrate completely and eat only protein food so that results can be measured accurately.

To convert protein to fat, it must first be converted into glucose and this conversion requires a high level of glucagon over insulin. This relativity can only occur when one has not consumed any food for 4-5 hours.

But to convert glucose into fat, high levels of glucagon over insulin must be present. A person hormonal balance can only be in this state when he has just eaten.

So theoretically, it is impossible for a person to be in both hormonal states at the same time. That being the case, how is it then possible for protein calories to be converted into body fat?