If you don’t drink coffee, you should think about two to four cups a day. It can make you more alert, happier, and more productive. It might even make you live longer. Coffee can also make you more likely to exercise, and it contains beneficial antioxidants and other substances associated with decreased risk of stroke (especially in women), Parkinson’s disease, and dementia. Coffee is also associated with decreased risk of abnormal heart rhythms, type 2 diabetes, and certain cancers.12, 13