There's increasing consensus that drinking coffee is mostly good for you. In addition to the physical boost it delivers, coffee also appears to lessen our risk of heart disease, diabetes, some cancers, dementia and Alzheimer's disease. It has been demonstrated, in studies, to improve both problem-solving and decision-making. And coffee may even help us live longer, according to a just-released British study involving nearly 500,000 adults in the U.K.