Coffee drinking 'increases arthritis risk'

Regular coffee drinkers may face a higher risk of arthritis in later life as well as theincreased possibility of heart disease and problems caused by excess caffeine.

Regular coffee drinkers may face a higher risk of arthritis in later life as well as theincreased possibility of heart disease and problems caused by excess caffeine.

Scientists have found coffee increased a hallmark early indicator, called the "rheumatoid factor".

Those on four or more cups a day were twice as likely to test positive for arthritis than occasional drinkers. Anyone putting down 11 or more cups a day was almost 15 times as likely to develop rheumatoid factor. The results held true even after adjusting for factors such as age, sex, smoking and weight. Researchers from the National Public Health Institute in Helsinki, Finland, had measured the rheumatoid factor in 7,000 people and checked their coffee habits.

None of a second group of 19,000 people monitored for 15 years had evidence of arthritis when first tested. The findings showed a strong association between coffee-drinking and rheumatoid factor.

The authors, writing in Annals of the Rheumatic Diseases, have not yet identified the ingredient in coffee, particularly unfiltered types, that could trigger the production of the factor, which can precede the development of arthritis by some years.

Most concern about coffee-drinking focuses on its caffeine content, although evidence suggests it almost certainly does more good than harm in moderate quantities, improving short-term memory, boosting muscle power and increasing alertness.

The question drinkers want to be answered is: how much is too much? Doctors are uncertain and the best advice is obvious but dull - moderation is the key.