People who drink 4 to 5 cups of coffee a day have the lowest overall risk of death. Once you hit 6 cups per day though, the risk of death actually starts to increase. That's most likely because consuming such a large amount of caffeine every day can greatly increase blood pressure problems and even lead to heart attack.
The bottom line is that drinking good amounts of coffee -- but not too much -- appears to lower your risk for diabetes, heart disease, stroke, infections, respiratory disease, and even injuries and accidents. This study did not show a strong link between coffee intake and reduced cancer risk (although there is some evidence that coffee intake protects against some forms of cancer).
One surprising finding is that decaf coffee appears to offer as much health protection as normal java. So the caffeine content probably isn't the main factor. Of course, another recent study showed that normal caffeinated coffee can significantly reduce the risk of depression so you might want to drink some to cover all of your bases!
Learn some mo': Coffee lovers less likely to die, study finds
