Coffee tastes bitter, so why do people drink?

This may seem counter-intuitive, but a new study reveals that people who are extremely sensitive to the bitter taste of coffee drink more.

This sensitivity is not simply a matter of taste, but rather is influenced by a person's genetic make-up, said the researchers in a study published online today (Nov. 15) in the journal Scientific Reports.

"You expect people who are particularly sensitive to the bitter taste of caffeine to drink less coffee," said lead researcher Marilyn Cornelis, assistant professor of preventive medicine at the Feinberg School of Medicine at Northwestern University in Chicago. a statement. . "The opposite results of our study suggest that coffee consumers acquire a taste [for] or an ability to detect [the bitterness of] caffeine because of the positive reinforcement learned, caused by caffeine. " [10 Things You Need to Know About Coffee]

In other words, people who have an increased ability to experience the bitterness of coffee, and particularly the distinctly bitter taste of caffeine, learn to associate with it "good things", said Cornelis. This discovery is surprising, as bitterness often serves as a warning mechanism to convince people to spit harmful substances, the scientists said.

The researchers conducted the study to understand the influence of genetics on the consumption of tea, coffee and alcohol, which tends to have a bitter taste, said Jue Sheng Ong, senior research fellow at the QIMR Berghofer Medical Research Institute PhD in Brisbane, Australia.

"Although all the bitter flavors may seem identical, we perceive separately the bitterness of Brussels sprouts, tonic water (quinine) and caffeine," Ong told Live Science. "The extent to which we find these bitter flavors is partly determined by your genes."

To investigate, the researchers examined the genetic makeup and daily consumption of bitter drinks from more than 400,000 people in the UK. "By using the genes related to our ability to taste bitterness, we were able to determine if those with a higher genetic predisposition to taste bitterness are more likely to prefer coffee tea," he said. Ong.

The results showed that people with genes to taste the bitterness of green vegetables (such as Brussels sprouts) or tonic water are more likely to prefer coffee tea, according to the researchers. In addition, people who are more sensitive to the bitter flavors of quinine and those in green vegetables tend to avoid coffee.

At the same time, researchers found that people with genes likely to taste the bitterness of Brussels sprouts were less likely to drink alcohol, especially red wine, than people do. not having these variants of the gene. This idea could help scientists who study addiction, said Ong.

Ong pointed out that researchers were not interested in flavors, such as cream or sugar, that people sometimes pour into coffee to lessen the bitterness. "One can imagine that, on a personal level, many factors determine a person's coffee consumption: socio-economic status, ability to metabolize caffeine and smoking," he said. "On top of that, people drink all kinds of coffee – black coffee, flat white [and] cappuccino. "Thus, the researchers chose to look for major trends in the relationship between genes and the consumption of bitter drinks, he said.

"[The results] suggest that perhaps most types of coffee still share very similar bitter taste profiles, "said Ong.

Originally published on Science live.