Obviously, humans need oxygen, that fact isn't lost on us, but often, the factors that get in the way of getting good oxygen are overlooked. A few well-known causes of fatigue, like anemia and iron deficiency, are actually oxygen problems even though we don't really think of them that way, but there are breathing related problems as well. The solution might just be as silly as taping your mouth shut.

If you're tired all the time, here are some factors to rule out at home or with your doctor.