find out why we shouldn't like coffee, but we like it

The more sensitive people are to the bitter taste of caffeine, the more coffee they drink, reports a new study. The sensitivity is based on genetics. Bitterness is natural warning system to protect us from harmful substances, so we really shouldn't like coffee. Scientists say people with heightened ability to detect coffee's bitterness learn to associate good things with it. Why do we like the bitter taste of coffee? Bitterness evolved as a natural warning system to protect the body from harmful substances. By evolutionary logic, we should want to spit it out.