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In a new study, researchers have been able to find specific gene variants that correlate with weight gain in some people.
CNN
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Obesity isn’t just about food and exercise – it may also be linked to your genetic code, a new study finds.
“The causes of obesity are very complex and in most cases result from a combination of many factors, but in this study we have found a clear genetic trigger for obesity,” Dr Mattia Frontini, senior fellow at the British Heart Foundation and associate professor of cell biology at the University of Exeter in the UK, and lead author of the study, said in an email.
The researchers used data from UK Biobank, a large biomedical database and research resource that follows people over time. According to a study published Thursday The researchers, published in the medical journal Med, compared data from people who had two defective copies of a particular gene (SMIM1) with those who did not have two defective copies.
The study found that women with the gene mutation gained 4.6 kilograms (10.14 pounds) in weight, while men gained 2.4 kilograms (5.29 pounds).
A defective copy of the SMIM1 gene causes reduced thyroid function and reduced energy expenditure. “This means that for the same food intake, less energy is used and the excess is stored as fat,” Frontini said.
“Not only is the correlation striking, but the study also identifies specific genetic variants, which is not always the case in studies,” said Dr. Philip Scherer, director of the Touchstone Diabetes Center at the University of Texas Southwestern Medical Center, who was not involved in the study.
“This is a very exciting study in that it puts a new gene on the map,” Scherer said, “This is not just a genomic locus that has had a mutation somewhere that we don’t understand, this is an actual gene. … We think we’re looking at a gene here that can be studied further.”
This particular gene finding doesn’t apply to the larger population of obese people, with only about 1 in 5,000 people having this genetic makeup, Frontini said.
“This is a fairly rare case, but when you multiply that by 10 million, 15 million people in the population, that’s a significant number of people living with this mutation who may not be aware of the fact that there is a genetic explanation for their struggle with obesity,” Scherer said.
Thyroid disorders are common, affecting around 2% of the UK population, and are regularly treated with relatively inexpensive medicines, Frontini said.
The next step in the research, he added, is to find out whether people with SMIM1 mutations are eligible for thyroid drug treatment.
“If so, we will conduct a randomized clinical trial to determine whether the treatment would benefit them,” Frontini says, “and if they do, we hope to be able to improve their quality of life with an inexpensive, safe treatment.”
Weight isn’t just a matter of willpower or laziness. Your body size and shape are determined by many factors, some of which you can control and some of which you can’t. National Institute of Diabetes and Digestive and Kidney Diseases.
According to the institute, these factors include lifestyle habits, amount of sleep, medications taken, health problems, where one lives or works, and genetics.
While research into genetic factors and potential treatments is still ongoing, Scherer said the current best approach to the medical treatment of obesity is GLP-1 drugs.
Strictly restrictive diets aren’t the answer, says Brooke Alpert, R.D., a registered dietitian and author of “Diet Detox: Why Your Food Is Making You Fat and What to Do About It.” Previous CNN article.
Demonizing food too much can make you crave it more, and the guilt you feel when you give in can send you into a vicious cycle of restricting and overeating, she adds.
If you want to make lifestyle changes, it’s best to take a gradual, sustainable approach that maintains a healthy relationship with food, Emily Feig, a postdoctoral researcher at Massachusetts General Hospital, said in the same CNN report.