The findings, which appear online in the journal BMJ, add to a growing body of evidence suggesting that moderate alcohol consumption may have health benefits.
Rheumatoid arthritis is an autoimmune disease that occurs when the body engages in friendly fire - attacking its own joints and tissues. According to the Arthritis Foundation, about 1.3 million people in the United States have rheumatoid arthritis, which disproportionately strikes women. Family history is a risk factor for developing the condition. Other than quitting smoking, little is known about how to lower the risk of developing rheumatoid arthritis.
How the study was done
The new study included more than 34 ,000 Swedish women born between 1914 and 1948. Researchers gathered information about their alcohol consumption, diet, smoking history, physical activity and education in 1987 and 1997. Participants were then followed for seven years. During this time, nearly 200 women were diagnosed with rheumatoid arthritis.
Women who reported drinking more than three glasses of alcohol per week in both 1987 and 1997 were 52 percent less likely to develop rheumatoid arthritis than their teetotalling counterparts.
A difference in risk, although less marked, existed when light drinkers were included with nondrinkers. In that case, women who drank more than more four glasses of alcohol per week had a 37% lower risk for rheumatoid arthritis.
These findings held regardless of whether women consumed wine, spirits or beer. In the study, a standard glass of alcohol was defined as approximately a pint of beer, 5 ounces of wine or 1.7 ounces of liquor.
Exactly how alcohol may lower arthritis risk is not fully understood. The researchers speculate that it may turn down the body's immune system and decrease the production of proteins involved in the inflammatory process. Inflammation is a hallmark of rheumatoid arthritis.
Benefits of alcohol
"This study adds more fuel to the fire regarding the beneficial effects of alcohol," said Dr. Martin Jan Bergman, a clinical associate professor of medicine at Drexel University College of Medicine in Philadelphia. "This is one of multiple studies that have shown that alcohol can have a beneficial effect on risk for [rheumatoid arthritis]."
But the key word is "moderate," he said.
Additionally, alcohol may do more harm than good for people who already have the condition. "A lot of [rheumatoid arthritis] medications are liver toxins and so is alcohol, so you have to weigh the risks and benefits if you are on any of these medications," he said.
Smoking and alcohol consumption often go hand-in-hand, said Dr. David Pisetsky, chief of rheumatology at Duke University Medical Center in Durham, N.C. "Stopping smoking or never starting is the best thing to do for your health if you are at risk for [rheumatoid arthritis]."
He added that "moderate alcohol [use] may also help lower this risk."
Although the study found an association between alcohol and rheumatoid arthritis risk, it did not prove a cause-and-effect relationship.
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