Metabolism and weight loss: How you burn calories - Mayo Clinic

You likely know your metabolism is linked to your weight. But do you know how?

Common belief holds that a slim person's metabolism is high and an overweight person's metabolism is low. But this isn't usually the case. Weight isn't necessarily directly linked to metabolism.

Instead, weight is dependent on the balance of total calories consumed versus total calories burned. Take in more calories than your body needs, and you gain weight. Take in less and you lose weight. Metabolism, then, is the engine that burns these calories....