Exercise can probably help you lose weight by burning a few more calories each day, if you at the same time consciously cut your calorie and carbohydrate intake. I say probably, because one of the surprising effects of exercise is that your metabolic rate decreases after exercise, so you burn fewer calories for several hours after exertion. This drop of metabolic rate makes sense if you are a caveman, and need to conserve calories after a hunt, as you need to stay alive, living on the brink of starvation. But the drop doesn’t help you lose weight. I never tell most patients not to exercise. Exercise increases your energy and your sense of well-being. But exercise probably won’t help you lose much weight, unless at the same time you keep your calories under 1500.