The thinness can be "in the genes", suggests a study

January 28, 2019

Scientists have identified several genetic variants that tip the scales in favor of thinness.

In the largest study of its kind, researchers at the University of Cambridge have studied people of different body types in order to search for genetic factors related to thinness. Previous studies have focused primarily on the search for genetic variants badociated with obesity or overweight. Many of these variants have been found, but few have been identified as being badociated with thinness.

"This study shows for the first time that healthy thin people are generally skinny because they have fewer genes that increase the risk of being overweight and not because they are morally superior, as some people do." suggest, "said Professor Sadaf Farooqi of the University of Cambridge, one of the leading researchers in the study. "It's easy to judge and criticize people for their weight, but science shows that things are much more complex. We have much less control over our weight than we might want to think.

Scientists recruited 2,000 thin people (defined as a body mbad index below 18) but healthy, with no health problems or eating disorders, and badyzed their DNA. They compared the DNA of 1622 of these volunteers to those of 1985 with severe obesity and 10,433 people of healthy weight.

They have identified several genetic variants already recognized to play a role in obesity, as well as some involved in thinness. They also found that three quarters of the volunteers in the thin cohort had a family history of leanness and health.

"As expected, we found that obese people had a higher genetic risk score than normal weight people, which contributes to their risk of being overweight. The genetic dice are laden against them, "said Dr. Inês Barroso of the Sanger Institute, another author of the journal.

Timothy Frayling, Professor of Human Genetics at the University of Exeter's School of Medicine, who did not participate in the research, said: "What's really interesting, is Is to be naturally thin seems to be largely the reverse of the genetic piece to be naturally overweight – the same genes seem to be involved, but in different forms. & # 39;

However, experts point out that genetic risk only increases the chances of being thin and that environmental factors, such as food and exercise, also play a major role. Tim Spector, professor of genetic epidemiology at King's College London, who was also independent of the study, said: "In most countries, about one third of people manage to stay lean despite exposure to poor food environments. This is due in part to genes, but other factors, such as individual lifestyle differences or intestinal microbes, are also likely to be responsible. "