The Right Way to Hydrate

By Heather Hurlock, DETAILS

Myth No. 1: You need to drink eight glasses a day to stay hydrated.
When researchers from the University of Pennsylvania attempted to track down the studies behind this recommendation, they couldn't find anything. It's an old wives' tale.

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Myth No. 2: When you're thirsty, you're already dehydrated.
As long as you drink when you're thirsty, you'll be fine. The Institute of Medicine's findings state that you can meet your daily hydration needs simply by letting thirst be your guide.

Myth No. 3: Caffeine dehydrates you.
Studies show that coffee and tea, like all fluids, hydrate just as well as water. Some studies even show that beer hydrates better than water, but remember: H2O is your best calorie-free, additive-free option.

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How much do you really need to drink?
To figure out how many ounces of water you'll require each day to stay hydrated, divide your body weight in half and drink that number of ounces. Add eight ounces for each half hour of exercise and bump that up to 16 if you're running for more than 45 minutes. As for electrolytes, you need only about 3.8 grams of salt to replace what you lose daily, which you probably get through normal eating. If you exercise for more than an hour, replace lost electrolytes with a drink containing carbohydrates and sodium. Rather than choosing from the rainbow array of sugar-sweetened artificial sports drinks, try coconut water, which has only one ingredient and nothing artificial.

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