/sci/ - Science & Math

>if you burn more calories than you eat, you lose weight.
No. The calorie as it is actually measured is not a complete representation of the energy in a food, and it especially is not a perfect representation of the energy one who eats it ABSORBS from food. So, you cannot calculate your energy intake. That is sad.
What about the other side of the equation? Energy expenditure. Can you calculate this? No. You cannot. Nobody can. Well, why not? I thought e^2=m^2c-blah blah shut up nerd, this is biology. The body does not operate on pure spherical point masses in a vacuum perfectly obliterating unobserved matter into pure energy. Duh.
>let's say i exercise/diet in such a way that i have a daily caloric deficit of X kcal/day
X will be different every single day. You mentioned you will exercise. let's assume this damages some muscles (the purpose of exercise) which will then be repaired and rebuilt (better, maybe even larger, assuming you're human) - then, obviously, your expenditure will be larger, as the body is spending resources to repair create maintain new muscle. You also cannot eat the same amount every day. Say you eat meat. The fat/protein content will be different. Say you eat plants. The number of cells ingested will be different. Your gut biome will be different. Your body will adjust, likely appearing to become more efficient with the new diet over time. Old families of microbes, starved from their perfect diet, will be outcompeted by "new" families.
I am sorry, but this is not science. This isn't science at all. If this were science, we could isolate variables. We could remove variables. We can't do that. It's not even possible to exercise the same amount every day, that would imply perfect time keeping, or from the other perspective perfect knowledge of your muscle size and status.
Observe that the alternative to what I have written here is that pro bodybuilders could become infinitely large (like your mother) and that pro anemics could become massless