Coffee can be bad for you but good for you at the same time. People can get most of their antioxidants from drinking coffee. Plus, since coffee has caffeine in it, it can keep you up if you drink it late at night. So, drink coffee six hours before you go to bed at the latest. Decaf coffee has chemicals in it and coffee was discovered by goats! Caffeine can kill you if you drink around 90 cups in one time! Two cups of coffee can cut post-gym muscle pain. Also, Decaf coffee has caffeine in it since if you drank five to ten cups of coffee, you would get the same amount of caffeine from drinking one cup. In conclusion, coffee is bad but good at the same time. Just don't drink a lot of coffee in one day and you'll be fine.
Source: http://www.livescience.com/health/080519-coffee-facts.html