Claim No. 5: Drinking Water Wards Off Headaches
Headache sufferers often blame water deprivation. But Goldfarb could only find one study that looked at this. The study participants who boosted their water intake had fewer headaches than those who did not, but the results were not statistically significant, meaning they could have been chance findings.
Second Opinion: Health Benefits of Drinking Water
The report provides interesting -- and sometimes surprising -- information, says David Baron, MD, a family physician and chief of staff at Santa Monica-UCLA Medical Center & Orthopaedic Hospital, Calif., who reviewed it for WebMD.
The most surprising finding, he says, was the lack of a scientific link found between drinking a lot of water in order to eat less. "I thought [the suggestion that] filling up your stomach with water might help lose weight makes sense," he says.
The report isn't dismissing the need to drink a healthy amount of fluids, he says. It simply showed no scientific basis to the recommendation to drink eight glasses of water daily.
"There is a lot of individual variation" in exactly how much water or fluid people need," he says.
Most of us, he says, are OK "by trusting our instincts" about how much to drink. "If you have a normal heart, normal kidneys, and normal thirst mechanism, it's not likely you will get dehydrated if there is a sufficient supply of fluids available," he says, and drink when thirsty.
Drinking Water: A Placebo Effect?
Might drinking a lot of water make us think we feel better, look better, and function better? Could there be a placebo effect to those eight daily glasses?
"I'm certain there is," Goldfarb says. "The placebo effect is very strong."
And if you're still convinced lots of water does your body good? No problem. "People say they feel stronger and healthier if they drink more water," he says. "That's fine. If they enjoy that benefit, so be it. [But] those who don't feel that way shouldn't feel obligated to drink the eight glasses."