Researchers have found even more evidence that coffee can be good for you. People who drink regular, moderate amounts of coffee are less likely to die from a range of diseases, from diabetes to heart disease.

The cutoff seems to be around five cups a day, and even decaf coffee helps, the team at Harvard University’s school of public health found.

But even heavy coffee drinking doesn’t appear to offset the damage caused by smoking, they report in the journal Circulation.

“The main message is that regular consumption, meaning three to five cups of coffee a day, is associated with lower risk in total mortality and mortality from several causes like diabetes, cardiovascular disease and suicide,” Frank Hu, a professor of nutrition and epidemiology who helped lead the study, told NBC News.

“In previous studies on that issue, most of the coffee was caffeinated coffee. In our study, both caffeinated and decaffeinated coffee showed a lower mortality risk but there is no final conclusion yet.”

Hu and colleagues looked at two giant sources of information: surveys of more than 200,000 doctors and nurses who have regularly updated researchers on their eating and other lifestyle habits and details about their health for more than 20 years.

Coffee drinkers overall were less likely to die over the decades than non-drinkers. The effects were even stronger and clearer when the team discounted smokers. Non-smokers who drank coffee were between 8 and 15 percent less likely to die, depending on how much they drank.

“This is good news for people who drink coffee because the evidence is strong. Drinking coffee may be good for health outcome,” Hu said.