Most of us have tried to lose weight at least once in our lives. We count calories, weigh every serving, give up our favorite foods, and exhaust ourselves with strict diets. But why is it that for some people, just looking at a dessert is enough to gain weight, while others can eat cake at night and stay slim?

We all know people who can eat cake all night and not gain weight, while others can gain weight just by looking at dessert. For decades, we’ve been told that the secret to weight loss is simple math: eat fewer calories than you burn.