• Posted October 4, 2023

Genes Might Be Driving You to Go Vegetarian

Going vegetarian is trendy and popular, along with being a healthy choice, but a large portion of those who say they want to stick with a plant-based diet don't.

It might come down to your DNA, suggests new research that has uncovered three genes that seem to be strongly linked to vegetarianism.

"It seems there are more people who would like to be vegetarian than actually are, and we think it's because there is something hard-wired here that people may be missing,"said corresponding study author Dr. Nabeel Yaseen, a professor emeritus of pathology at Northwestern University Feinberg School of Medicine in Chicago.

As many as 48% to 64% of people who identify as vegetarian still report eating fish, poultry and/or red meat, the study authors pointed out in a university news release.

To study the impact of genes on eating behavior, the scientists compared UK Biobank genetic data from more than 5,300 strict vegetarians -- those who ate no fish, poultry or red meat -- to more than 329,000 non-vegetarians (the "control" group).

The investigators found 31 genes that are potentially associated. Several of these genes, including two of those most closely associated, are involved in metabolizing fat and/or brain function.

"One area in which plant products differ from meat is complex lipids,"Yaseen said. "My speculation is there may be lipid component(s) present in meat that some people need. And maybe people whose genetics favor vegetarianism are able to synthesize these components endogenously. However, at this time, this is mere speculation and much more work needs to be done to understand the physiology of vegetarianism."

About 3% to 4% of Americans are vegetarian. Religious and moral considerations factor into whether or not to eat meat.

Yaseen said that the driving factor for food and drink preference is not just taste, but how an individual's body metabolizes it. Most people don't find alcohol or coffee pleasant at first, but they may develop a taste over time because of how these drinks make them feel, he noted.

"I think with meat, there's something similar. Perhaps you have a certain component -- I'm speculating a lipid component -- that makes you need it and crave it,"Yaseen explained.

"While religious and moral considerations certainly play a major role in the motivation to adopt a vegetarian diet, our data suggest that the ability to adhere to such a diet is constrained by genetics,"Yaseen added. "We hope that future studies will lead to a better understanding of the physiologic differences between vegetarians and non-vegetarians, thus enabling us to provide personalized dietary recommendations and to produce better meat substitutes."

All of the study participants were white so the results wouldn't be misconstrued because of race or ethnicity.

The findings were published Oct. 4 in the journal PLOS ONE.

More information

The Academy of Nutrition and Dietetics has more on vegetarianism.

SOURCE: Northwestern University, news release, Oct. 4, 2023