Researchers have discovered a “clear genetic trigger for obesity” that applies to some people

Obesity isn’t just a matter of diet and exercise — it may be in your genetic code, according to new research.

“The causes of obesity are very complex and, in most cases, the combination of many factors. In this study, however, we found a clear genetic trigger for obesity,” said study lead author Dr. Mattia Frontini, a senior researcher at the British Heart Foundation and associate professor of cell biology at the University of Exeter in the United Kingdom, in an e-mail. .

The researchers used data from the UK Biobank, a large biomedical database and research resource that follows people long-term, according to the study published Thursday in the journal Med. They compared data from people with two faulty copies of a specific gene (SMIM1) and those that did not have the two defective copies.

Women with the genetic mutation weighed an extra 4.6 kilograms (10.14 pounds) and men with the variant weighed an extra 2.4 kilograms (5.29 pounds), according to the study.

Defective copies of the SMIM1 gene cause decreased thyroid function and decreased energy expenditure, Frontini said, “which means that given the same food intake, less energy is used and this excess is stored as fat.”

Not only is the correlation significant, but this study also identifies a specific genetic mutation, which is not always the case in research, said Dr. Philipp Scherer, director of the Touchstone Diabetes Center at the University of Texas Southwestern Medical Center. He was not involved in the study.

“It’s an interesting study because it puts a new gene on the map,” Scherer said. “It’s a real gene, not just a genomic locus with a mutation somewhere that we don’t understand. … We think we’re looking at a gene that we can study more deeply.”

This genetic finding is ‘very rare’

This specific genetic finding doesn’t apply to a large population of people with obesity — only about 1 in 5,000 people has this genetic makeup, Frontini said.

“That’s very rare, but you multiply that by a population of 10 (million), 15 million and there are some people out there who would walk around with that mutation and maybe not be fully aware of the fact that there is a genetic. explanation for his fight against obesity,” said Scherer.

Thyroid dysfunction is common, affecting almost 2% of the population in the UK, Frontini said. And thyroid dysfunction is regularly treated with a relatively inexpensive medication, Frontini said.

The next step in the research is to find out whether people with the SMIM1 mutation qualify to treat their thyroid with medication, he added.

“If they do, we plan to conduct a randomized clinical trial to determine whether they would benefit from the treatment,” Frontini said. “The hope is yes, and that we can improve their quality of life through cheap and safe treatment.”

The best approach in the meantime

Weight is not just a matter of willpower or laziness. Your body size and shape are determined by many factors – some of which you have control over and some of which you don’t, depending on the National Institute of Diabetes and Digestive and Kidney Diseases.

Among these factors are lifestyle habits, amount of sleep, medications, health problems, where you live and work and genetics, according to the institute.

Research into genetic factors and potential treatments is still ongoing, but Scherer said the best current approach to medically treating obesity is GLP-1 medications.

Severe restrictive diets are not the answer, said Brooke Alpert, registered dietitian and author of “The Diet Detox: Why Your Diet Is Making You Fat and What to Do About It,” in a previous CNN article.

Demonizing foods too much can make you crave them more, and then the guilt you feel when indulging can lead to a cycle of oscillating between restricting and bingeing, she added.

If you want to make changes to your lifestyle, it’s best to try a gradual, sustainable approach while maintaining a healthy relationship with food, said Emily Feig, a postdoctoral fellow at Massachusetts General Hospital, in the same CNN report.

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