Why do we like bitter drinks? Not taste, genes suggest

Sweet beverages or bitter ones? Our preference between them results from variation in genes related to their psychoactive properties, not those related to taste, research finds.

Scientist Marilyn Cornelis searched for variations in our taste genes that could explain our beverage preferences, because understanding those preferences could indicate ways to intervene in people’s diets.

“The genetics underlying our preferences are related to the psychoactive components of these drinks,” says Cornelis, assistant professor of preventive medicine at Northwestern University Feinberg School of Medicine. “People like the way coffee and alcohol make them feel. That’s why they drink it. It’s not the taste.”

The paper appears in Human Molecular Genetics.

Mystery gene

The study highlights important behavior-reward components to beverage choice and adds to our understanding of the link between genetics and beverage consumption—and the potential barriers to intervening in people’s diets, Cornelis says.

Sugary beverages are linked to many disease and health conditions. Alcohol intake is related to more than 200 diseases and accounts for about 6 percent of deaths globally.

Cornelis did find one variant in a gene, called FTO, linked to sugar-sweetened drinks. People who had a variant in the FTO gene—the same variant previously related to lower risk of obesity—surprisingly preferred sugar-sweetened beverages.

“It’s counterintuitive,” Cornelis says. “FTO has been something of a mystery gene, and we don’t know exactly how it’s linked to obesity. It likely plays a role in behavior, which would be linked to weight management.”

“To our knowledge, this is the first genome-wide association study of beverage consumption based on taste perspective,” says Victor Zhong, the study’s first author and postdoctoral fellow in preventive medicine at Northwestern. “It’s also the most comprehensive genome-wide association study of beverage consumption to date.”

Bitter drinks vs. sweet drinks

The researchers categorized beverages into a bitter-tasting group and a sweet-tasting group. Bitter included coffee, tea, grapefruit juice, beer, red wine, and liquor. Sweet included sugar-sweetened beverages, artificially sweetened beverages, and non-grapefruit juices.

The team collected beverage intake using 24-hour dietary recalls or questionnaires. Scientists counted the number of servings of these bitter and sweet beverages that about 336,000 individuals in the UK Biobank consumed. Then they did a genome-wide association study of bitter beverage consumption and of sweet beverage consumption. Lastly, they looked to replicate their key findings in three US cohorts.

Support for the research came from the American Heart Association Strategically Focused Research Networks; the National Institute on Deafness and Other Communication Disorders; the National Institutes of Health; the National Heart, Lung and Blood Institute; and the National Cancer Institute of the NIH.

Source: Northwestern University