Men who drink six or more cups of coffee a day are nearly 60 percent less likely to develop lethal prostate cancer, according to researchers at Harvard. In a study of nearly 48,000 U.S. males from 1986 to 2008, Harvard researchers found that coffee made a critical difference; even three cups a day led to a 30 percent lower risk of deadly prostate cancer. The findings were reported in the most recent edition of the Journal of the National Cancer Institute. On the other hand, a 2007 study from Dartmouth medical school found that people who drank 4 or more cups a day had a 35 percent decrease in insulin sensitivity, which increases the risk of diabetes.
