Why do some foods taste bitter to certain people?

The ability to taste bitterness varies significantly between people due to genetic differences in taste receptor genes, particularly TAS2R38. People often called "supertasters" have more taste buds and heightened sensitivity to bitter compounds like those found in Brussels sprouts, coffee, and dark chocolate. About 25% of people are supertasters, 50% are medium tasters, and 25% are non-tasters who barely detect bitterness at all. The specific gene variants a person inherits determine how strongly their taste receptors respond to different bitter molecules. This is why cilantro tastes soapy to some people, or why certain individuals find tonic water unbearably bitter while others enjoy it. Age, smoking, and medications can also alter bitter taste perception over time.