Epigenetics would be a determining factor in overweight and obesity in women

Epigenetics is the science that studies the influence of the environment on gene expression. Researchers have discovered that it could be involved in excess weight.

A risk of overweight increased by 44%

According to their work, published in the journal Science Translational Medicine, the risk of being overweight in women would be increased by 44% in those who carry a large number of methyl groups attached to the sequence of the gene which codes for proopiomelanocortin (POMC), a protein precursor which is involved in the feeling of satiety. To reach this conclusion, the scientists analyzed the expression of the gene which encodes the POMC in more than 1100 people. They found that obese women with a BMI greater than 35 had more methyl groups attached to the satiety gene sequence, compared to women with a normal weight.

Methyl groups are fine chemical units that the body uses to mark letters in the genetic code to turn genes on or off without changing the DNA sequence. Simply put, DNA methylation turns genes off, in a stable but potentially reversible way. We are talking about epigenetic marks. In this specific case of methylation of the POMC gene, this has the effect of extinguishing the feeling of satiety and therefore of increasing food intake.

Lifestyle remains the biggest risk factor for overweight and obesity

“This 44% increase in obesity risk is similar to obesity risk in people with predisposing genes”, said Professor Peter Kühnen, lead author of the study. “But this increased risk is lower than that linked to lifestyle, which can increase the risk of obesity by two or three. As for DNA methylation, which we have observed only in women, we do not yet know how to explain this phenomenon.“, he added.

This “formatting” of the POMC gene would take place at the start of the embryo’s development, shortly after the egg and the sperm have fused into a single cell.

Previous studies have shown that the presence or absence of certain nutrients may have a role to play in epigenetic mechanisms. These nutrients are betaine (a plant substance found in beets), methionine (found in meat, fish, eggs, dairy products, cereals and soybeans) and folic acid (found in green vegetables and red fruits).

To recognize satiety, you must first have experienced the feeling of hunger (gurgling stomach, feeling of an empty stomach, slight fatigue, etc.). If, during your meal, the food becomes less tasty, you eat more slowly, you begin to feel tired and feel the need to leave the table, you have eaten enough. The signs of satiety can vary from one individual to another, the best is to listen to his feeling of hunger. On the other hand, if you feel heavy at the end of the meal and you feel an overflow of the stomach, it means that you have exceeded the satiety threshold.