Caffeine and diabetes: Helpful or harmful?

James Lane, PhD, Duke University, describes numerous studies that have demonstrated caffeine's potential for increasing insulin resistance (impaired glucose tolerance) in adults that do not have diabetes, an effect that could make susceptible individuals more likely to develop the disease. In adults with type 2 diabetes, studies have shown that the increase in blood glucose levels that occurs after they eat carbohydrates is exaggerated if they also consume a caffeinated beverage such as coffee. This effect could contribute to higher glucose levels in people with diabetes and could compromise treatment aimed at controlling their blood glucose.

"More than 220 million people worldwide have diabetes, says Editor-in-Chief Jack E. James, PhD, School of Psychology, National University of Ireland, Galway, Ireland. "The links that have been revealed between diabetes and the consumption of caffeine beverages (especially coffee) are of monumental importance when it is acknowledged that more than 80% of the world's population consumes caffeine daily. Dr. Lane's review of the topic gives the clearest account to date of what we know, what we don't know, and what needs to be done -- urgently!"