fats. That's just to get it into your blood from your intestines.

Quick biochemistry lesson: It's all about the adenosine triphosphate (ATP). Your body burns carbs, fats, and some proteins to create ATP which is the form the energy is actually used in.

it's a return on investment. Each cell has to first use an ATP to begin the process of breaking down sugar to eventually build up ATP stores.

To burn fat for energy, you're body has to spend more ATP to get the fat's ready to enter the Kreb's cycle and build up the ATP stores.

100 Calories worth of sugar will actually provide your body with more ATP (energy) than 100 calories of fat.


also a quick side note, if you look into all the biochemistry of all this. When you lose weight, you lose it mostly through the CO2 you breath out, (and the water that was in your fat stores)