The ideal weight is considered today as a high. In a world where calories are in oodles available, but at the same time heavy physical work is still done, many people spend their life in a rollercoaster of different diets. Usually without lasting success. It must not be due to a lack of will power, if one decreases. Two studies in the journal “Cell” show that the genes play an important role.
Both studies work with the data from the UK Biobank. Half a Million people over the age of 40 to 69 years, have provided the Biobank, their DNA samples and medical records available. So their health can be tracked over a number of years.
Thin due to a lack of appetite Gene
Here, the researchers came across a group of people who have been their whole life long thin. And that’s not a special metabolism, these people are just interested in eating, never think of the next meal. A genetic change dampens your appetite.
The key is a genetic feeling of Hunger, or the Lack thereof. And this feeling is triggered by the “Hunger”Gene MC4R. Dr. Sadaf Farooqi, Professor of metabolism and medicine at the University of Cambridge, has conducted research for 20 years on the MC4R. Approximately 300 different mutations in this gene. The mutations here are for six percent of the children suffering from severe obesity. These mutations destroy the feeling of satiety and Fullness after a meal. Normally, the Gene should be send after a meal is a Signal that says: Now it is enough! But a Mutation in the MC4R under this message is suppressed. The result is that Despite a full stomach, these individuals always feel hungry,
In the new study, Dr. Farooqi has not been discovered now that some of the thin people there’s something wrong with MC4R. Here’s the “I’m full”Signal due to a Mutation is always active. These people feel never hungry. After all, six percent of the population “suffering” of this Mutation. “Our study shows that genetics plays an important role in why some people are obese and some people are lucky enough to have genes that protect them from obesity,” said Professor Farooqi. “This does not mean that we can’t affect our weight, by watching what we eat, but it means that some people have a worse Chance than others.”
Gen-Score is determined by the weight
The second study took advantage of the Biobank data, to reliably and quickly predict who is fat and who is spared from weight problems. Dr. Amit V. Khera has set up an obesity risk score, which is based on DNA changes in the genome. 2.1 million genetic variants in the Score. People with high risk values of 15 kilograms heavier than those with low values.
In Parallel, the researchers supplemented the adult data of the Biobank with the values of children. At birth, the genes have no influence on the weight. However, already at the age of three and a half years, children with a high Score were significantly heavier. With eight years, these children were often obese. At the end of puberty, you had 15 kg more on the Ribs than others.
With a high-risk core you are not doomed to obesity, but a high value means that there is probably a life-long struggle to maintain a healthy weight, regrets Dr. Khera. Some people with a high genetic Score have, nevertheless, weights, normal Body, but these people need to work harder in order to keep a healthy weight than others, says Dr. Khera. The difference between a good and a bad Obesity-THEN-Score corresponds, on average, about five BMI points. “Five points are a lot,” says Dr. Khera. “That takes a person from normal to obese, or from obese severely obese.”
Sources: Sciencedaily / Cell Human Gain-of-Function MC4R Variants Show Signaling Bias and Protect against Obesity / Cell Polygenic Prediction of Weight and Obesity Trajectories from Birth to Adulthood / science news