LONDON – Regular alcohol consumption provided protection against rheumatoid arthritis and its painful effects, British researchers found in the first study to show the link in humans.

Non-drinkers were four times more likely to develop rheumatoid arthritis than people who drank alcohol on more than 10 days a month, according to the research published online today by the journal Rheumatology. Arthritis patients who drank regularly had less severe symptoms than non-drinkers, the study found.

There is no known cause or cure for rheumatoid arthritis, according to the National Institute for Health and Clinical Excellence. The disease occurs when the immune system attacks the joints, causing pain and swelling and potentially leading to severe disability and early death. Alcohol blunts the activity of the immune system, and more research is needed to determine how that process works, the researchers said.

“We know that alcohol reduces immune activity at least to some extent, and suspect that this is the main reason that alcohol consumption is associated with a reduction in severity” of rheumatoid arthritis, said James Maxwell, a rheumatologist at the Rotherham Foundation NHS Trust and author of the study. “Alcohol may also have a mild pain-killing effect,” he said.

Researchers compared 873 rheumatoid arthritis patients in Sheffield, England, to 1,004 people without the illness. The participants answered a questionnaire, had X-rays and blood tests taken and had their joints examined. Those taking part in the study were asked how often they drank alcohol in the month before their inclusion in the study.