Coffee tastes bitter, so why do we drink it?

People who are more sensitive to the bitter taste of coffee (and caffeine) actually drink more coffee, latest research studies show. Scientists explain that instead of negative (because of the bitter taste), these people associate positive feelings for it (because of the positive reinforcement elicited by caffeine). This is a bit counter-intuitive because bitter taste, usually serves as a warning mechanism to convince people to spit out harmful substances.

Researchers concluded that we perceive the bitterness of different substances (like Brussels sprouts, tonic water (quinine) and caffeine) separately and the degree to which we find these flavors bitter is, in part, determined by our genes. In the study, researchers looked at the genetic makeup and daily bitter-beverage consumption of more than 400,000 people from the United Kingdom.

The results showed that people with the genes to taste the bitterness of green vegetables (such as Brussels sprouts) or tonic water are more likely to prefer tea over coffee, and people who were more sensitive to quinine’s bitter flavors and those found in green vegetables tended to avoid coffee. At the same time people with the genes to taste the bitterness in Brussels sprouts were less likely to drink alcohol, especially red wine, than people without those gene variants, the scientists found.