People who consumed at least four cups of coffee per day had a 64% lower risk of all-cause mortality than those who never or almost never consumed coffee. There was a 22% lower risk of all-cause mortality for each two additional cups of coffee per day. There was a significant interaction between coffee consumption and age. In those who were at least 45 years old, drinking two additional cups of coffee per day was associated with a 30% lower risk of mortality. The association was not significant among younger participants.