Why do People Drink Coffee despite its Bitter Flavor?

Contrary to popular belief, those who are extremely sensitive to the bitterness of coffee actually consume more of it. The study, which was published in the journal Scientific Reports, found that this sensitivity is not only a question of taste but rather is influenced by a person’s genetic make-up.

Those who are especially sensitive to the harsh taste of caffeine should probably drink less coffee, right? According to the contrary findings of our research, caffeine users may develop a liking for it or the ability to recognize its bitterness as a result of the acquired positive reinforcement it causes.”

Evolution is thought to have favored people who were able to sense bitterness. Considering that dangerous compounds like alkaloids that are present in poisonous plants are frequently the cause of acute and unpleasant tastes.

The popularity of coffee, however, has long perplexed experts. Coffee is one of the most popular drinks in the world despite the fact that its bitter flavor should, in theory, cause people to react negatively. A recent study’s authors think they may have discovered the reason why, despite coffee’s bitterness, people like to drink it.

Researchers from QIMR Berghofer Medical Research Institute in Australia and Northwestern University Feinberg School of Medicine in Chicago, IL, collaborated to investigate the connection between a person’s genetic susceptibility to bitter substances and the amount of bitter beverages they consume.

How does Taste Work?

Although taste has been extensively investigated, we still don’t fully understand how it works. We desire a biological perspective to comprehend it. One study, which was published in the journal Scientific Reports, makes use of two sets of data. The first dataset was compiled from a sizable study of Australian twins that revealed a relationship between genetic variations and how individuals evaluated various flavors.

In three substances—caffeine, quinine, a component of tonic water, and PROP, another bitter chemical found in some vegetables—researchers focused on specific versions they thought were responsible for a heightened experience of bitterness.

The UK Biobank, a research facility that houses blood, urine, and saliva samples from tens of thousands of people, provided the second dataset. The research team combined self-reported responses from a questionnaire regarding beverage use with more than 400,000 male and female samples.

The study compared gene variations with how frequently the same individuals consumed coffee, tea, and alcohol using a natural experimental technique called Mendelian randomization. A heavy coffee consumer was defined as one who consumed more than 4 cups per day, and a heavy tea drinker consumed more than 5 cups per day. Heavy drinkers were defined as individuals who consumed alcohol more than three or four times per week.

The Power of Caffeine

Researchers found that a person who was more sensitive to the caffeinated beverage’s harsh flavor consumed more coffee. Conversely, those who were more sensitive to quinine and PROP reported consuming less coffee.

PROP was the only drug that clearly affected alcohol consumption; tea had the reverse effects. Less alcohol was consumed by those who could quickly identify the substance. The researchers of the study believe they may have figured out why heavy coffee users tend to be those who are more sensitive to the bitter taste of caffeine.

Caffeine’s stimulating effects on the brain have been thoroughly studied by scientists, leading them to the conclusion that this reaction serves as a sort of positive reinforcement. It is therefore feasible that habitual coffee drinkers learn to recognize caffeine or just develop a taste for it.

According to first author Jue Sheng Ong, “this study provides some answers regarding why certain people are at increased risk of heavy use of these bitter drinks,” noting that the study also offers some intriguing findings beyond coffee.

“You were more likely to choose a cup of tea than coffee if you were genetically predisposed to taste the bitterness in brussels sprouts. The same was true for red wine; those who disliked items high in PROP were also less likely to like a glass of red.

Future Prospects on the Research

There are certain restrictions on these results. If there is a causal relationship between genes and certain taste impressions, more study is required to confirm it. It will be important to conduct more research to establish if non-European populations exhibit the similar trends.

In spite of any potential detrimental health effects, this study may help to understand why certain people find it difficult to resist particular drinks. Therefore, the researchers who oversaw the study intend to explore the connection between flavor perception and health in more detail.

Ong pointed out that flavorings like cream or sugar that people occasionally add to coffee to lessen its harshness were not examined by the researchers. According to him, a person’s coffee consumption is likely influenced by a variety of personal factors, including socioeconomic position, a person’s capacity to metabolize caffeine, and smoking. “On top of that, people drink all other kinds of coffee, including cappuccino, flat white, and black coffee.” Hence, he said, the scientists decided to seek for broad trends in how genes link to the use of bitter beverages.