The question

Coffee drinkers swear by the pick-me-up they get from their daily cup (or two or three) of coffee. Might the benefit of regular coffee consumption extend beyond this energy boost?

This study

The researchers analyzed data on 451,743 adults, most in their early 50s at the start of the study. During the next 16 years, 41,693 people died. Those who regularly drank the most coffee were the least likely to have died. Compared with those who did not drink coffee, men who consumed three or more cups a day were 18 percent and women 8 percent less likely to have died. The risk reduction applied to both caffeinated and decaffeinated coffee consumption. Coffee drinking appeared particularly protective against death from digestive diseases (especially for men) and circulatory diseases (especially for women).

Who may be affected?

Coffee drinkers. An estimated 83 percent of American adults drink coffee, and 54 percent drink it daily, averaging three nine-ounce cups a day. Earlier studies have linked coffee consumption with such health benefits as protection from Parkinson’s disease, Type 2 diabetes and liver disease, improvement in cognitive function and a reduced risk for depression. Negatives associated with coffee drinking stem mainly from its caffeine content (about 95 milligrams per eight-ounce cup) — which can disrupt sleep and cause anxiety — and from calories from added cream and sugar.


Coffee consumption data came from the participants’ responses on questionnaires or during interviews. A correlation between longer life and coffee drinking should not be taken as causation. An editorial that accompanied the study described the association between coffee drinking and mortality as “modest” and said that “recommending coffee intake to reduce mortality or prevent chronic disease would be premature.” The study is one of many done over the years on coffee; some show mild benefits, some show mild risks.

Find this study

Online July 11 in Annals of Internal Medicine (annals.org; click on “Latest”)

Learn more

Information on the effects of coffee can be found at hsph.­harvard.edu (search for “coffee & health”) and at eatright.org (search for “java”).

The research described in Quick Study comes from credible, peer-reviewed journals.