临床研究发现：饭前喝两杯水有助减肥

Does Drinking Water Before Meals Help You Lose Weight?
Two glasses before meals may help you shed pounds permanently

Drinking two 8-ounce glasses of water before breakfast, lunch, and dinner may be just the backstop your willpower needs to help you shed pounds permanently in 2011, according to a recent study published in Obesity. Researchers instructed two groups of overweight or obese men and women to follow a low-calorie diet, asking one group to also drink two cups of water before meals. After 12 weeks, the water drinkers had lost an average of 15½ pounds, compared with 11 pounds for the control group. Those who continued the habit for a year lost an additional 1½ pounds on average. "I would never promote this as a get-slim-quick scheme," says senior study author Brenda Davy, an associate professor in the department of human nutrition, foods, and exercise at Virginia Tech University, who notes that the practice slows the emptying of the stomach. "This is simply an additional strategy that could help people manage their hunger."

The study examined the effect only on middle-age and older adults, but Liwei Chen, an assistant professor of epidemiology at Louisiana State University Health Science Center School of Public Health, thinks it's a smart strategy for everybody, particularly if it causes them to cut back on soda. American adults average 28 ounces of sugar-sweetened beverages per day, says Chen, who led a study published in May that found even a small reduction in sugar intake significantly lowered blood pressure. "Aim to avoid sugar-sweetened beverages altogether," she advises. That way, you battle two risk factors at once.

- By Hanna Dubansky （US News，Health）