Knowing the glycemic impact rating of foods, too, is very helpful. More so than knowing just the calorie and/or carbohydrate content. But, yeah, as Mlle has pointed out, metabolism is a vastly complicated process, varies genetically by individual as to normative functioning, and there are a ton of things that affect it, like medications, environmental toxin exposures, and tumors that form on metabolically important glands, as happens in Cushing's Disease. Physical activity is inseparable from metabolism. It's the main reason metabolism exists; to provide the energy that cells and the body structures they form need to allow bodily movement and growth towards pursuing survival. So, when I read silly posts from the fringes about how exercise is oppressive....no. It is not. Take a walk or a wheelchair roll, or you will gradually kill off years of your inherited lifespan potential.
