Coffee occupies a unique space in nutrition and health research. First, it is widely consumed globally; in the United States, for example, 3 of 4 adults report drinking coffee,1 making it potentially important for public health. Second, coffee drinking is often a daily, and likely a long-term, habit, making it potentially important for individual health. Because coffee is consumed regularly, it is likely captured with relatively little measurement error by self-report1; consequently, studies of coffee with mortality and incident disease are less prone to measurement error–induced bias than those of other nutritional exposures. Finally, unlike intake of other foods with perceived health benefits, coffee drinking is usually positively correlated with chronic disease risk factors, including age, cigarette smoking, and alcohol drinking, contributing to long-standing concerns that coffee drinking might increase the risk of cancer and other chronic diseases.