The American Dietetic Association offers the following images as a guide to determining portion sizes. The Heart and Hand Newsletter reports that there is a more precious formula for good health than simply drinking eight glasses of water than simply drinking eight glasses of water a day. For example, a person who weighs 180 pounds should drink 90 ounces of water a day or roughly 12 eight-ounce glasses. A 130 pound woman should drink 65 ounces- which does work out to the traditionally prescribed eight glasses. And for every alcoholic or caffienated beverage you drink, plan on drinking an additional glass to combat dehydrating effects.
Nicotine is by far the most dehydrating effects.
If you're a smoker, you ought to drink a glass of water for every cigarette. The Surgeon General has determined that lack of physical activity is the equivalent of smoking a pack of cigarettes a day. Click on the box.