Scientists say that they have discovered the secret of why some people are thin, while others easily hit the pounds.
Their work reveals newly discovered genetic regions that are very slim.
The international team says that this supports the idea that for some people it is more important to inherit "happy" genes than to have a perfect diet or a perfect lifestyle.
The study appears in PLOS Genetics.
In recent decades, researchers have found hundreds of genetic changes that increase the likelihood that a person is overweight. However, the focus is less on the genes of people who are thin.
In this study, scientists compared DNA samples from 1
They also looked at lifestyle questionnaires to rule out eating disorders, for example.
Researchers found that people who were overweight were more likely to have a number of genes related to obesity.
Meanwhile, people who were thin had not only fewer genes associated with obesity, but also changes in gene regions newly associated with healthy thinness.
& # 39; Rush to judgment & # 39;
Senior researcher Sadaf Farooqi of the University of Cambridge called on people to judge the other's weight less.
"This research shows for the first time that healthy, thin people are usually thin because they have less exposure to genes that increase a person's chances of overweight and not because they are morally superior, as some people like claim." She said.
"It's easy to judge and criticize people because of their weight, but science shows that things are much more complex.
" We have far less control over our weight than we might think. "19659005" Scientists say the next step is to identify the exact genes involved in healthy thinness.
Your longer-term goal is to see if this new knowledge can help propel new weight-loss strategies
19659014] Commenting on the research, Professor Tom Sanders, emeritus professor of nutrition and dietetics at King's College London, said: "This is an important and well-conducted study, which confirms that premature severe obesity is often genetic and convincing It is amazing that those who are very thin are genetically different from the general population. However, he added: "Most obesity is acquired in adulthood and is related to the obesogenic environment in which we live – a sedentary lifestyle and a rich access to calorie dense foods.
Prof Tim Spector, also from King's College London, said that a third of people in most countries remained slim despite everything.
" Some factors are due to genes, other factors like The individual is probably also responsible for differences in lifestyle or intestinal microbes, "he said.
Health experts say, regardless of their shape or genetic makeup, the age-old advice of healthy exercise levels and nutrition is still present.