A recent study has shown that thin people have certain gene regions in their DNA that keep them lean, while fewer gene variants have been linked to obesity.
"We found that there are genes associated with thin space," said Sadaf Farooqi, a professor of metabolism and medicine at Cambridge University who led the study.
The motivation of the study was to help people who are struggling with weight. "It's easy to judge quickly and criticize people for their weight, but science shows that things are much more complex," said Farooqi. "We have much less control over our weight than we might want to think," she said.
Previous studies, for example, with twins, have shown that body weight differences in the same environment are due to genes, the authors write. "Genes play at least 40% of people's weight," Farooqi told CNN. "It's much more than people realize."
Genetic Risk Score
To study the link between genes and weight, Farooqi's team compared the DNA of some 14,000 people.
A group of 1,622 thin participants with a body mass index of 18 or less but no eating disorders or medical conditions were discontinued. They were compared to 1985 severely obese individuals with a body mass index of over 40 and 10 433 normal weight, whose body mass index was 19-25.
DNA samples were taken from the saliva or blood of participants and the team looked for genetic variants that were previously identified as overweight or obese.
By adding more than 100 different genetic variants, the team identified a genetic risk score and found that obese people had a higher genetic risk score than normal or thin people, which is not surprising, Farooqi said.
On the other hand, this risk score was "very low in thin people," so they have far fewer genes that contribute to obesity compared to the rest of the population, which they explained. "They dropped a bullet."
"Thinness is inheritable trait "
The Farooqi team also found new genetic regions involved in healthy thinness. Not only do thin people stay "slim" because they do not have the genes for obesity, they also have other genes that protect them from gaining weight, she said.
The study concludes that "thinness like obesity is inheritable."
Obesity-related illnesses such as heart disease, stroke, or type 2 diabetes are among the leading causes of death worldwide, according to the study.
One potential limitation of the study, according to Farooqi, is that her team found genetic regions rather than finding specific genes that keep people thin. "
The next step is finding these specific genes, she said," If we can find the genes that prevent people from gaining weight, "we can target them to find new weight-loss strategies and help people Farooqi said,
Tim Spector, a professor of genetic epidemiology at King's College London, agreed that the study highlights what we have known from twin studies over the past 15 years Genetics is important for your tendency to be thin or obese. In general, thin people are more likely to have multiple thin relatives and obese people. "
Spector, who was not involved in the research, added the genes found in this study" supplement the list from larger studies and are helpful for understanding of mechanisms. "But" do not help "in individual predictions of obesity, he said in an email to CNN." In most countries, about a third of people manage to stay thin, even though they are in one genes are bad genes, but other factors such as individual lifestyle differences or intestinal microbes are probably responsible, "said Spector.
Challenging assumptions about weight
The new paper" Calls for Automatic Assuming some "overweight people are lazy or have willpower, and that is a positive thing, but we know There are factors other than genetics in determining the weight of a patient, such as the diet and how often he trains, "Dr. Steve Mowle, honorary treasurer of the Royal College of GPs in the UK, in an email to CNN. He cautioned that although the study suggests that leaner humans are genetically predisposed to lower risk of obesity, "the risk factors of an unhealthy lifestyle are the same."
. "GPs recommend everyone to maintain a healthy lifestyle for their patients, regardless of their weight or genetic make-up, including ensuring that patients are well-balanced, exercising regularly, drinking alcohol in moderation, not smoking, and getting enough sleep." Mowle said he was not involved in the research.