Two new studies suggest that drinking alcohol can help ward off two diseases that affect millions of women: rheumatoid arthritis and osteoporosis. But the study is just one of several that paint a confusing picture of how alcohol affects women's health. Doctors say the key, as always, is moderation.
One of the studies investigated alcohol consumption and its effect on rheumatoid arthritis in more than 34,000 Swedish women between ages 54 and 89. The researchers had contacted the women in 1987 and 1997, surveying them about their alcohol use. Then they started keeping close tabs on the women, scouring Swedish national registries for those who were diagnosed with rheumatoid arthritis between 2003 and 2009.
The women who reported moderate alcohol consumption -- those drinking 17 ounces of beer, 5 ounces of wine or 1.7 ounces of liquor three times or more each week -- had a 52 percent decreased risk of developing rheumatoid arthritis compared with those who never drank at all.
The researchers noticed that the women who drank more alcohol were also more likely to smoke, which is a risk factor for rheumatoid arthritis. But they found that moderate drinking reduced the risk for current smokers to 33 percent, though the benefits of the alcohol were not as marked for smokers as for never-smokers, for whom moderate drinking reduced RA risk by 62 percent.
The study was published Tuesday in the British Medical Journal.
"Our results suggest that moderate alcohol consumption of alcohol, approximately half a glass of alcohol per day, may reduce the risk of developing RA," especially when women don't smoke, said Daniela Di Giuseppe, the study's lead author and a doctoral student at the Karolinska Institute in Stockholm.
A small group of women in Oregon who had a few drinks each week also seemed to benefit in a surprising place: their bones.
Researchers at Oregon State University studied 40 postmenopausal women under age 65 who reported drinking up to two drinks per day in the year before the study, watching what happened when they asked these women to stop drinking for two weeks.
When these regular moderate drinkers cut out alcohol, the researchers found that their blood showed higher levels of biomarkers linked to bone turnover, a natural process that goes awry when more bone is lost than is replaced, which leads to osteoporosis. When the women started drinking again, their bone turnover seemed to improve even after one day of moderate alcohol consumption.
Ursula Iwaniec, one of the authors of the study, published today in the journal Menopause, said alcohol seemed to benefit these postmenopausal women, but it may not be the best solution for women hoping to improve their bone health.
"I wouldn't start drinking just for this reason that it's going to make my bones better," she said.
That moderate drinking seems to affect women's health is not surprising. Alcohol raises levels of estrogen, the hormone that affects many aspects of women's health, including arthritis and osteoporosis. Alcohol also raises the "good" cholesterol, HDL, and can have positive effects on blood pressure and other risk factors for cardiovascular disease.