Coffee is in the science news again, with two interesting papers that document its benefits. Both were recently published in the American Journal of Clinical Nutrition. The first paper adds more evidence that drinking coffee reduces the risk of type 2 diabetes. The study involved 69,532 French women who were observed over an 11 year period. The authors report an “inverse association [diabetes]…for both regular and decaffeinated coffee and for filtered and black coffee, with no effect of sweetening. Total caffeine intake was also associated with a statistically significantly lower risk of diabetes. Neither tea nor chicory consumption was associated with diabetes risk.” Interestingly, the authors also noted that the observed benefit was particularly pronounced with coffee consumed at lunch. Their conclusion: “Our data support an inverse association between coffee consumption and diabetes and suggest that the time of drinking coffee plays a distinct role in glucose metabolism.”

Considering the importance of inflammation in chronic disease, the second paper is especially interesting in that it documents reductions in subclinical inflammation and oxidative stress as mechanisms by which coffee lowers the risk of type 2 diabetes. Noting that “Coffee consumption is associated with a decreased risk of type 2 diabetes,” the authors state that their “aim was to investigate the effects of daily coffee consumption on biomarkers of coffee intake, subclinical inflammation, oxidative stress, glucose, and lipid metabolism.” They observed a number of interesting effects, including beneficial lowering of the LDL/HDL ratio and IL-18, and an increase in adiponectin. Meanwhile, no adverse changes were seen on the oral glucose tolerance test. They conclude: “Coffee consumption appears to have beneficial effects on subclinical inflammation and HDL cholesterol, whereas no [adverse] changes in glucose metabolism were found in our study.”