Some People Are Genetically 'Hardwired' To Find Vegetables Bitter and Avoid Them, Scientists Say

Some people are "hardwired" not to like vegetables like broccoli, sprouts, and cabbage, because of their genetic make-up, according to research.

The study involved 175 people, with an average age of 52. These participants, who had two or more risk factors for cardiovascular disease, filled out a questionnaire about what they ate per day, including vegetables. They also had their genes mapped.

Researchers looked at which copies of the TAS2R38 taste gene they inherited. People with the AVI variant aren't known to taste bitterness when they encounter certain chemicals found in vegetables. Those with one AVI and another known as PAV do taste bitterness, but such chemicals taste extremely bitter to those with two copies of PAV.

The data showed PAV carriers were more than 2.6 times less likely to eat the most vegetables in the study group when compared with other participants.

Jennifer L. Smith, Ph.D., R.N., study author and a postdoctoral fellow in cardiovascular science at the University of Kentucky School of Medicine in Lexington, explained in a statement: "We're talking a ruin-your-day level of bitter when they tasted the test compound. These people are likely to find broccoli, brussels sprouts and cabbage unpleasantly bitter."

Past research has suggested the gene could make chocolate, coffee, and beer taste more bitter, Smith told Newsweek, but this wasn't tested in the study.

The authors of the reserach worry this variant could put people off eating vegetables which could protect their heart health.

The preliminary research is due to be presented at the American Heart Association's Scientific Sessions 2019, and hasn't been published in a peer-reviewed journal.

Smith told Newsweek: "This study adds to the debate of whether the gene is influential in dietary choices and eating behavior of people with the bitter tasting version of this gene.

"Some studies have shown it does, other have shown it does not. Our study adds to the notion that it is influential in how much people with the bitter tasting gene eat vegetables,"she said.

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A stock image shows a woman who is repulsed by salad. Scientists believe some people may have a genetic sensitivity which may put them off vegetables. Getty

Smith acknowledged the study was limited because the participants were all Caucasian. "This was done to control for population stratification of the gene. Future studies should endeavor to have a more diverse sample," she said.

But Smith argued the work could still help in seeing genetics used to tailor how patients learn what to eat according to their unique genotype.
"Knowing that specific things may taste a specific way to a person allows us to gear our education to help them adapt to a heart healthy eating pattern," explained Smith.

The take-home message, she said, is that taste matters when trying to change your diet and that taste can be affected by genotype. This can be picked up with a standard genotype tests, she said.

"So for some people, not liking certain vegetables is a hardwired response brought about by the genes. It's helpful to know this so they can choose other vegetables to improve their diets," said Smith.