Study findings indicate that those who drank coffee at the beginning of a 13-year study had a slightly lower risk of death than others, whether they chose decaf or full-strength.

Coffee drinkers also were a little less likely to die from heart disease, respiratory problems, strokes, injuries and accidents, diabetes and infections although the association was not seen for cancer.

But the benefits were modest – even among those with the heaviest coffee habit. Men who drank six or more cups of coffee day had a 10% lower overall risk of death than those who drank no coffee, while women who drank a similar amount had a 15% lower overall risk of death, according to the study.

Researchers caution, however, that they can’t be certain whether these associations mean that drinking coffee actually makes people live longer.

“Coffee is one of the most widely consumed beverages in America, but the association between coffee consumption and risk of death has been unclear. We found coffee consumption to be associated with lower risk of death overall, and of death from a number of different causes,” said Neal Freedman, from the National Cancer Institute, “Although we cannot infer a causal relationship between coffee drinking and lower risk of death, we believe these results do provide some reassurance that coffee drinking does not adversely affect health.”

The investigators caution that coffee intake was assessed by self-report at a single time point and therefore might not reflect long-term patterns of intake. Also, information was not available on how the coffee was prepared (espresso, boiled, filtered, etc.); the researchers consider it possible that preparation methods may affect the levels of any protective components in coffee.