Do you ever find yourself craving something sweet even after a big meal? Or wonder how you still have room for dessert despite feeling full? Researchers now suggest that the phenomenon known as “dessert stomach” is linked to the brain.
In a recent study, researchers investigated the phenomenon in mice and found that they ate sugar even when they were full. While analyzing the brains, they discovered that a group of nerve cells called POMC neurons triggered the craving for sugar.
When the mice ate sugar, these neurons released ß-endorphin, a natural opiate that made them feel rewarded and caused them to eat more, even if they were full. This effect was specific to sugar, not other foods. When the researchers blocked this pathway, the mice stopped eating extra sugar, but only when they were full. The inhibition of the ß-endorphin did not affect the hungry mice.
The researchers also found that the activation of endorphins began even before the mice started eating sugar, as soon as they sensed it. Interestingly, the opiate was also released in the brains of mice that had never eaten sugar before.
“As soon as the first sugar solution entered the mice’s mouths, ß-endorphin was released in the “dessert stomach region”, which was further strengthened by additional sugar consumption,” the researchers explained.
When a similar trial was conducted in humans, researchers used brain scans on volunteers after they received a sugar solution through a tube. They found that the same region of the brain responded to sugar in humans where there are many opiate receptors close to satiety neurons.
“From an evolutionary perspective, this makes sense: sugar is rare in nature but provides quick energy. The brain is programmed to control the intake of sugar whenever it is available,” explained Henning Fenselau, research group leader at the Max Planck Institute for Metabolism Research and head of the study.
The researchers hope their findings could be valuable for treating obesity. “There are already drugs that block opiate receptors in the brain, but the weight loss is less than with appetite-suppressant injections. We believe that a combination with them or with other therapies could be very useful. However, we need to investigate this further,” Fenselau added.
