Whether people prefer coffee or tea may boil down to a matter of taste genetics.
People with a version of a gene that increases sensitivity to the bitter flavor of caffeine tend to be coffee drinkers, researchers report online November 15 in Scientific Reports. Tea drinkers tended to be less sensitive to caffeine’s bitter taste, but have versions of genes that increase sensitivity to the bitterness of other chemicals, the researchers found.
It’s long been thought that people avoid eating bitter foods because bitterness is an indicator of poison, says John Hayes, a taste researcher at Penn State who was not involved in the study. The coffee and tea findings help challenge that “overly simplistic ‘bitter is always bad, let’s avoid it’” view, he says.