Coffee drinkers appear to be at increased risk of developing rheumatoid arthritis, according to a study in the Annals of the Rheumatic Diseases. People who drank four or more cups of coffee a day had twice the risk and those who consumed 11 or more cups had 15 times the risk of developing rheumatoid arthritis.
Finnish scientists at the National Public Health Institute in Helsinki reported that “the number of cups of coffee drunk daily was directly proportional to the prevalence of RF (rheumatoid factor) activity.”An as yet unidentified ingredient in coffee, especially in the unfiltered variety, may trigger the production of rheumatoid factor, which can precede the development of arthritis by years, and consequently lead to an increased risk of rheumatoid arthritis.
The findings are based on surveys of two groups, one a cross-sectional survey of almost 7000 people and the other a group of almost 19,000 people followed over a 15 year period, none of whom had any evidence of arthritis when first tested. The results were consistent even after adjusting for other risk factors, such as age, gender, smoking and weight. The scientists found that 126 people developed the disease and 89 had rheumatoid factor antibodies at the time they were diagnosed.
Rheumatoid Arthritis is a systemic autoimmune disease that affects one to two percent of the population. It appears to hit women the hardest, with an estimated 22.8 million female sufferers in the United States alone. When the body’s immune system is not functioning correctly, healthy joint tissue comes under attack. Joint damage and inflammation of the joint linings cause pain, stiffness and swelling. It is a complex disease and scientists have yet to determine a specific cause, although genetics and the environment are thought to be key factors.
The Coffee Science Information Center, based in the U.K., takes another view of scientific papers as a whole, commenting that “the results of one paper can never tell the whole story. Taken as a whole, the results of thousands of investigations do not show that coffee is bad for the health.”
Coffee Science Information Center