The report on coffee, published in the Archives of Internal Medicine, was based on the results from 18 studies, which included a total of nearly 458,000 people. A combined analysis of the findings identified a significant relationship between coffee-drinking and reduced risk of diabetes:
Health concerns about coffee drinking are most often related to its caffeine content. Caffeine can temporarily increase heart rate and blood pressure, cause irritability and insomnia, and trigger irregular heart rhythms in some people. There is also evidence that women who drink caffeinated beverages might have a harder time achieving and maintaining pregnancy. On the other hand, research suggests that coffee drinkers might be at lower risk of developing gallstones, colon cancer, Alzheimer’s disease, and Parkinson’s disease. It may also prevent liver damage in people at high risk of liver disease.
“Our findings suggest that any protective effects of coffee and tea [against diabetes] are unlikely to be solely effects of caffeine but rather, as has been speculated previously, they likely involve a broader range of chemical constituents present in these beverages, such as magnesium, lignans, and chlorogenic acids,” the authors of the current report noted in their conclusion.
While drinking coffee, decaf, and tea might help prevent diabetes, the best ways to avoid this increasingly common disease are eating a healthy diet and getting regular exercise:
(Arch Intern Med 2009;169:2053–63)