There's a right—and wrong—way to follow one.

This article was reviewed by Craig Primack, MD, FACP, FAAP, FOMA. You’ve heard the saying “calories in versus calories out” when it comes to weight loss. This is referring to a calorie deficit. But ...

Losing fat is simple (in theory). If you use more calories than you eat you will eventually lower your body fat. It’s called a “Calorie Deficit” and it really is that simple. But why are gyms the ...

Calorie deficits may stall when intake is inaccurately tracked or metabolism adapts. Sleep, protein intake and hormones (such as insulin, leptin and ghrelin) heavily influence fat-loss success.