Some Harvard study found that downing 1-3 cups of coffee a day can reduce diabetes risk by single digits, while 6 cups or more daily slashed men's risk by 54% and women's by 30% over those who drink something else. Several studies suggest coffee is far more healthful than harmful. In general very little bad and a lot of good comes from drinking coffee, but there are exceptions. Coffee drinkers are up to 80% less likely to get Parkinson's, have a 25% reduced risk of colon cancer, an 80% drop in liver cirrhosis risk. Some research indicates coffee may help manage asthma, stop a headache, boost mood, and prevent cavities. Coffee is the #1 source of antioxidants in the American diet; black tea seems to come in second.
Still, that crumpet study seems worth looking into.