When we are stressed we tend to throw ourselves on comfort foods. If it feels good at the time, scientists have found that it gradually creates a preference for sweet foods and leads to weight gain.
Who has never rushed to the packet of granola or the tub of vanilla ice cream to comfort themselves in times of stress? This craving for comfort foods in times of stress is known to scientists: stress consumes a lot of energy and this reward that we give ourselves in the form of fatty and sugary foods helps to calm down and reboost.
However, Australian researchers warn of the long-term consequences on the metabolism of this mode of reward in the event of chronic stress.
Chronic stress disables the satiety process
“Stress combined with high-calorie comfort foods creates changes in the brain that encourage more eating, stimulate cravings for sugary and highly palatable foods, and lead to excessive weight gain,” explain researchers from the Garvan Institute in Sydney.
In a study conducted on mice subjected to stress and various diets, they found that an area of the brain known as the lateral habenula (which turns off the brain’s reward response), remained active in mice. on a short-term high-fat diet to protect them from overeating. But in chronically stressed mice, this part of the brain remained silent, allowing reward signals to remain active and continue to encourage pleasure eating.
“We found that stressed mice that ate a high-fat diet gained twice as much weight as mice that ate the same diet and were unstressed.” explain the scientists.
Stress leads to a preference for sweets
The researchers then performed a “sucralose preference test”, allowing the mice to choose to drink either water or water that had been artificially sweetened.
“Stressed mice on a high-fat diet consumed 3 times more sucralose than mice on the same diet but unstressed. This suggests that stress not only activates reward signals but specifically elicits cravings. sweet and palatable foods,” add the Sydney researchers.
Source : Critical role of lateral habenula circuits in the control of stress-induced palatable food consumptionNeuron, June 2023