Coffee and Caffeine FAQ

Interesting. Although could it be that a large portion of the non-coffee drinking suicide population were depressed people. Most depressed people know it is bad for them to have caffeine, or too much of it, and thus do not drink it. Therefore instead of higher suicide rates among non-coffee drinkers than coffee drinkers, is it possible that this large population group included more  depressed people who committed suicide than just being people that did not drink coffee?