Science suddenly seems to have a java jones. Four new studies focus on Americas favorite morning brew, adding to the overflowing cup of research linking coffee consumption to health benefits.Three of the studies examine, at least in part, the possibility that coffee might help protect against diabetes-an idea backed by several previous reports. The E3N/Epic Cohort Study adds support to such a benefit, but finds that when you drink coffee makes a difference: In an analysis of data on 69,532 French women, ages 41 to 72, over an average 11 years, Franoise Clavel- Chapelon, PhD, of INSERM and colleagues concluded that those drinking three or more cups of coffee daily were 27% less at risk for type-2 diabetes. But the association was limited to coffee consumed at lunchtime, leading researchers to speculate that the time of drinking coffee plays a distinct role in glucose metabolism.A new clinical trial, however, finds no impact on glucose metabolism but does support a beneficial effect of coffee on cholesterol levels and inflammation. Kerstin Kempf, PhD, from the German Diabetes Center in Dsseldorf and colleagues had 47 coffee drinkers kick the habit for a month, then ramp back up to four cups daily the next month and eight cups the third month. As the subjects increased coffee intake, HDL (good) cholesterol increased and subclinical inflammation-a risk factor for diabetes- improved, but there was no change in how the body handles sugar.Then theres the Strong Heart Study of 1,141 American Indian men and women, ages 45-74. In this population particularly at risk for diabetes, those drinking the most coffee-a whopping 12 or more cups daily- were 67% less likely to develop the disease than non-coffee consumers over an average 7.6 years. Overall, a high level of coffee consumption was associated with a reduced risk of deterioration of glucose metabolism-a precursor of diabetes.If all this tempts you to plug in the coffee pot, take heart-literally. Research presented at a recent American Heart Association conference reports that coffee drinking isnt associated with a greater risk of heart arrhythmia. In fact, contrary to popular belief, researchers say people who drink four or more cups of coffee daily were actually 18% less likely to be admitted to the hospital for a heart-rhythm disturbance than coffee abstainers. Arthur Klatsky, MD, of Kaiser Permanente and colleagues confess to being surprised by their results, because patients sometimes report forceful heartbeats or palpitations after drinking coffee.If you have trouble tolerating caffeine or coffee, the scientists add, their study shouldnt change the advice to avoid both, nor should you take up the habit in hopes of preventing arrhythmias. But moderate coffee drinkers should take comfort in the results. Sorry, tea lovers, the seven-year study of 130,054 men and women found no similar benefit for tea drinking.TO LEARN MORE: American Journal of Clinical Nutrition, April 2010; abstracts at www.ajcn.org/cgi/content/ abstract/91/4/1002 and www.ajcn.org/cgi/content/ abstract/91/4/950. Nutrition, Metabolism and Cardiovascular Diseases, online ahead of print; abstract at dx.doi.org/10.1016/j.numecd.2009.10.020.
