What does it mean exactly to have a 'fast metabolism'?

But despite excuses like "I have a slow metabolism," in the grand scheme of things, metabolic rate doesn't vary much from person to person. ... read more

But fast metabolism (aka, fast oxidizer) can also refer to a metabolic type defined by, among other things, the speed at which carbohydrates are mobilized and burned. read more

Your metabolism refers to all of the chemical processes that go on inside your body to keep you alive, according to the U.K.'s National Health Service. read more

Metabolism refers to the collective chemical processes that convert food into energy. Similar to gas for your car, food is your body's fuel. If you have a fast metabolism, your body lacks fuel efficiency. Compared with someone with a normal or slow metabolism, your body is not as efficient at converting food into usable metabolic energy. read more