Coffee contains antioxidant that our body needs, however, if you find yourself needing coffee every day and when you don't get your coffee fix you feel low and lack energy it may be a sign of dependence.  I didn't believe it at first but there have been cases where individuals have developed an addiction and/or dependence on caffeine.  Too much of anything is bad, too much caffeine can increase chances for heart related illnesses.

This addiction can be difficult to diagnose since caffeine is in many drinks like coffee, tea and soda.  The amount we consume is not of our concern most do not realize they have developed an abnormal use.  Caffeine is not a drug or illegal so I can't be addicted -- is what most would say.  Building tolerance toward the effects of caffeine can be dangerous, tolerance means that it takes more cups or coffee or more tea bags for us to feel the effects.   Caffeine addiction can bring severe side effects such as irritability, headaches,extreme fatigue, and sleepiness.