Engineering360: "We Should Hate Coffee. Study Explores Why We Love It."

A significant fraction of coffee drinkers add sugar or cream or another flavoring which will help hide the bitterness. For some, "Coffee is the medication of choice for ADHD."

So true about coffee and ADD or ADHD. Caffeine apparently has a paradoxical effect on those with ADD. A therapist friend of mine informally uses this paradoxical reaction to caffeine as an informal marker for the syndrome.