A group of scientists at Cambridge University say they have discovered the secret of why some people are weak while others gain weight very easily.
His work reveals the existence of newly discovered genetic regions related to subtlety.
The international team claims that its findings confirm the idea that for some people, thinness has more to do with the succession of a bunch of "lucky" genes rather than following a perfect diet or lifestyle.
- Countries where there is too much obesity and malnutrition (and which are in Latin America)
The study was published in an open-access scientific journal PLOS Genetics.
Over the last decades, several researchers have discovered hundreds of genetic changes that increase the chance of being overweight.
Much less attention is paid to studying the genes of people who are thin.
To carry out this study, UK scientists used DNA samples from 1600 healthy, thin people who had a body mass index (BMI) of less than 18.
They compared these samples with those of 2000 severely obese and 10,400 people with normal weight.
They also use and analyze lifestyle questionnaires to exclude, for example, the existence of eating disorders.
Researchers have found that people who are overweight they are more likely to have a set of overweight related genes.
In so many people who were thin, not only did they have fewer excess weight genes, but they also showed changes in the genetic regions that are recently associated with healthy finesse.
The chief researcher, Professor Sadak Faruki of the University of Cambridge, asked people to be less prejudiced by the weight of others.
"This study shows for the first time that thin and healthy people are usually weak because they have a lower load of genes that increase the chances of being overweight and not because they are morally superior"as some people say," he said.
"It's easy to rush to judge and criticize people for their weight, but science shows that things are much more complicated."
"We have far less weight control than we would like to believe."
Scientists say the next step is to accurately identify the genes involved in the healthful finesse.
Its longer-term goal is to see if this new knowledge can help with configuration new strategies for weight loss.
Tom Sanders, an honorary professor of nutrition and dietetics at King's College London, told the study: "This is an important and well conducted study that confirms that early heavy obesity is often genetically determined."
He added that he also "convincingly shows that those who are very weak are genetically different from the population."
However, he explained: "The majority of obesity is acquired in adulthood and is related to the obsessional environment we live in: a sedentary lifestyle and rich access to dense calorie food".
- Why can not you be obese and healthy at the same time?
Professor Tim Spectrum, also from King's College London, noted that around one-third of the people in most countries managed to remain weak.
"Some of this is due to genes, but other factors, such as Individual differences in lifestyle or intestinal microbes, they are probably also responsible, "he said.
Health experts stress that in any case, regardless of the size of your body or genetic makeup, the old advice is to follow a good diet and do a healthy exerciseIt is still recommended.
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