Drink Up to Slim Down?

"When did we start to drink anything other than water and [as babies] breast milk?" asks Popkin, co-author of a system to help consumers make smarter choices about beverages. "We didn't even have many caloric beverages 150 years ago, except a little bit of beer and a little bit of alcohol. We're really talking about a new addition to the human race."

That addition is often loaded with calories. Research suggests that at least half the excess calories consumed by Americans are sipped or swilled, not eaten. From 1977 to 2001, U.S. consumption of just two popular beverages -- juice and soft drinks -- nearly tripled, going from an average intake of 50 calories per day to nearly 155 calories. That increase could be enough to gain 15 pounds per year.

What's more, the brain doesn't seem to register liquid calories as accurately as calories that are chewed, and it doesn't send satiety signals to stop consumption of other food.

Why? "We don't know," says Barbara Rolls, professor of nutrition at Pennsylvania State University. "Hunger and thirst are controlled by separate mechanisms. At what point does food become a beverage or beverage a food? We don't know."

Knowing the smartest ways to quench your thirst without widening your waistline can be confusing. Here are a few ways to make your favorite beverages -- and perhaps you -- a little skinnier:

· Love your latte ? A 16-ounce latte with whole milk packs 260 calories. Even a skim latte contains 160 calories. Choose a skim cafe au lait the same size and shave 70 more calories. Or have a skim 16-ounce cappuccino, which has just 100 calories.

· Sip only unsweetened fruit juice. Limit to four ounces per day. Want more? Stretch those four ounces by adding it to sparkling water.

· Switch from 2 percent milk to skim. Doing just that saves 42 calories per eight ounces.

· Drink water, not sports drinks, for workouts. Unless you exercise for an hour or more, you don't need to replace sodium and other electrolytes lost through sweating.

· Green tea isn't always low-calorie. A grande Starbucks Blackberry Green Tea Frappuccino Blended Creme Whip has 560 calories and 15 grams of fat. Better choice: a large mug of green tea with a dab of honey and lemon. Calories: 20 to 30, depending on how much honey you use.