Issue 130 Item 7 High Coffee Consumption Reduces Risk of Type 2 Diabetes

Drinking more than seven cups of coffee per day may reduce the risk of type 2 diabetes. That, according to the results of a prospective population study reported in the Nov. 9 issue of The Lancet.

"Coffee is a major source of caffeine, which has been shown to acutely reduce sensitivity to insulin, but also has potentially beneficial effects," write Rob M. van Dam and Edith J.M. Feskens from the Dutch National Institute for Public Health and the Environment in Bilthoven, the Netherlands. They suggest that magnesium in coffee could improve insulin sensitivity and excretion, and that other components of coffee such as chlorogenic acid could also lower risk of diabetes.

In a population-based cohort of 17,111 Dutch adults aged 30 to 60 years, there were 306 new cases of type 2 diabetes during 125,774 person-years of follow-up. Individuals who drank seven or more cups of coffee daily were 50% less likely to develop type 2 diabetes compared with drinkers of two cups daily, even after adjustment for confounding factors including smoking, alcohol consumption, and body mass. Relative risk for high coffee consumption was 0.50 (95% confidence interval, 0.35-0.72, P=.0002).

"In view of the widespread use of coffee and the large health burden of type 2 diabetes, our finding of an inverse association between coffee consumption and risk of type 2 diabetes could have important public health implications," the authors write. "However, our findings need to be replicated and possible adverse effects on other health aspects should be considered in the choice to consume coffee." Lancet. 2002;360:1477-1478