Popeye Was Right

Yup, eat your spinach (or other green leafy vegetable of choice)! Inorganic nitrate, which is found in such fruits and vegetables, can help increase mitochondrial efficiency. Why do we care about this? Basically, it translates into a reduction in oxygen consumption during exercise, as well as protection against heart disease and diabetes. But, while the effects of inorganic nitrate seem to have a rather immediate effect, the long-term benefits have not yet been studied.

Just make sure your mouth wash isn't too strong, or you might not be getting all of the benefits of a well-balanced diet (read the last paragraph of the article... now there's a random aside for ya!).