Drink to Your Health

Your daily water supply comes from three sources, and you lose water in four principal ways. The percentages shown here are averages for nonexercisers. Runners sweat more, and need to drink more, than nonexercisers.

Actual percentages will vary considerably, depending on the weather, your diet, the amount you exercise, and other factors. *Approximately 10 percent of your daily water supply comes from metabolic water, which is water that's "liberated" within the body when you burn fats and carbohydrates.