In just a few days, an ultra-transformed and hypercalorical diet alters the brain response to insulin and modifies eating behavior, which can increase the risk of obesity and diabetes.
- A study reveals that in just five days, an ultra-transformed diet rich in calories alters the brain’s response to insulin and modifies eating behaviors.
- Researchers have observed, in good healthy men, an increase in fat in the liver and disturbances in the brain reward system.
- These effects, close to those observed in obese people, do not completely disappear after a week of return to normal food, which highlights the importance of monitoring its diet, even in short periods.
We know that eating too fatty and too sweet promotes obesity and diabetes, among other chronic diseases. But a new study reveals that the effects do not wait for months to manifest itself: in just five days, an ultra-transformed and calorie diet could alter the brain response to insulin and promote unbalanced eating behaviors. Details were published in the journals Nature And Metabolism nature.
Prolonged effects on the brain
Researchers at the Helmholtz Center in Munich and the University of Tübingen, Germany, carried out a study on 29 young and healthy men (19-27, BMI between 19 and 25). They divided the participants into two cohorts: a test group subject to a very caloric diet (+1,500 kcal/day in the form of ultra-transformed snacks) and a control group retaining its usual diet.
After five days, although the weight of the participants has not changed significantly, brain imagery revealed a modification of the brain sensitivity to insulin, indicates a press release. In parallel, the fat rate in the liver increased, from 1.55 % to 2.54 %.
In detail, the researchers analyzed brain activity by functional MRI before, just after experimentation, then a week after returning to normal diet. They found that the response to insulin increased in certain areas (right island cortex, left roland inside, cerebral trunk). After a week, it nevertheless decreased in a marked manner in other regions involved in cognition (right hippocampus, bilateral fusiform gyrus).
An influence on motivation and eating behavior
Another major discovery of the study concerns the brain reward system, which plays an essential role in food choices. To assess this function, scientists have used a behavioral reinforcement test (“Go/no-go“) Measuring sensitivity to rewards and punishments.
Participants subject to the hypercaloric diet showed a decrease in reaction to rewards and an increase in sensitivity to punishment. In other words, they were less motivated by the awards and more inclined to avoid the negative consequences. However, these changes, similar to those observed in people in obesity, have not completely disappeared a week after returning to normal diet.
What long -term health impacts?
These results are disturbing because they suggest that a simple period of food overconsumption can permanently disrupt the mechanisms of appetite regulation and pleasure associated with food. Ultimately, this could promote harmful eating habits and increase the risk of obesity and diabetes. A balanced diet and regular physical activity remain the best weapons to preserve both our brain and our metabolism, conclude the authors of the study.
