LOMA LINDA, Calif. (AP) -- Drinking five glasses of water a day can lower the risk of deadly heart disease, according to a study released Thursday.
Researchers at Loma Linda University said people who drank five eight-ounce glasses of water daily were about half as likely to die of coronary heart disease as those who drank two glasses or less.
The benefit was greater than that conferred from drinking a moderate amount of alcohol or taking aspirin, the study said.
In fact, drinking water appears to confer as much a benefit to heart health "as stopping smoking or lowering cholesterol," said Dr. Jacqueline Chan, the study's lead author.
"This is a really simple method" of preventing coronary heart disease, she said.
Coffee, soda, milk and caffeinated sodas did not show any statistically significant heart benefits.
Chan said more research is needed to confirm the findings, but researchers already adjusted the figures to account for other potential factors in heart disease fatalities such as smoking, calorie intake, exercise, blood pressure, and socio-economic status.
The study, which was to be published in the American Journal of Epidemiology, did not specifically explain how increased water-drinking might lower the risk of heart disease. But it noted that dehydration can elevate risk factors such as blood viscosity.
The study also suggested that those who drank more water might be more health-conscious.
However, Chan said drinking more water now couldn't hurt.
"There's no downside to increasing fluid intake," Chan said.
The study was based on a 1970s survey of Californians living in Seventh Day Adventist households and on follow-ups. The water study analyzed data from 12,017 women and 8,280 men, ages 38 or older, who had no physician-diagnosed heart disease, stroke or diabetes in 1976.
It found that in the six years following the original survey, 246 died of coronary disease, and those people were significantly more likely to be water sippers than water gulpers.
Men who drank five glasses of water or more per day were only 46 percent as likely to die of coronary disease as men who drank two or less.
For women, heavy water drinkers were 59 percent as likely to die of heart problems. But unlike men, they saw about the same benefits if they drank only three or four glasses per day, the study concluded.
