Scientists closer to understanding ‘dessert stomach’ phenomenon
Scientists from the Max Planck Institute for Metabolism Research in Cologne have discovered why many crave something sweet straight after a large meal, even while feeling full. And the reason lies within the nervous system.
The need for something sweetNerve cells that signal fullness also trigger cravings for sweet flavours. That’s according to a new study out of Germany.
Labelled the ‘dessert stomach’ phenomenon, people often find themselves reaching for something sweet after a filling meal. This, the researchers claim, is because the same nerve cells responsible for signalling fullness after a meal also play a role in triggering a craving for sweet foods and beverages.
To investigate the underlying reason for this, the research team studied mice and found that even when fully satiated, they continued to consume sugary foods.
Brain analyses of the mice revealed that a specific group of nerve cells, known as POMC neurons (Hypothalamic pro-opiomelanocortin), were responsible for this response. These neurons became active as soon as the mice were exposed to sugar, enhancing their appetite despite prior fullness.
When mice are full and eat sugar, these nerve cells not only release signalling molecules that stimulate satiety, but also one of the body’s own opiates – ß-endorphin. This acts on other nerve cells with opiate receptors and triggers a feeling of reward, which causes the mice to eat sugar even beyond fullness. This opioid pathway in the brain was found to be specifically activated when the mice ate additional sugar, but not when they ate normal or fatty food.
Scientists discover link between nerve cells that signal fullness and cravings for sweet flavours. (Image: Getty/wundervisuals)Furthermore the researchers found that this mechanism was already activated when the mice viewed the sugar, before eating it.
The opiate was also released in the brains of mice that had never eaten sugar before.
As soon as sugar entered the mice’s mouths, ß-endorphin was released in the ‘dessert stomach’ region, which was further strengthened by additional sugar consumption.
When the researchers blocked this pathway, the mice refrained from eating additional sugar.
This effect was only observed in full animals. In hungry mice, the inhibition of ß-endorphin release had no effect.
Effects on humansThe team also carried out studies on humans, finding that the same region of the brain reacted to sugar.
“From an evolutionary perspective, this makes sense,” says Henning Fenselau, research group leader at the Max Planck Institute for Metabolism Research. “The brain is programmed to control the intake of sugar whenever it is available.”
Potential obesity treatmentThe research team believe these findings could be important for the future treatment of obesity.
“There are already drugs that block opiate receptors in the brain, but the weight loss is less than with appetite-suppressant injections,” says Fenselau. “We believe that a combination with them or with other therapies could be very useful.”
However, the team says that further investigation into the effects of sweet flavours on the brain is required and are already planning future studies.
Scientists uncover reasons behind “dessert stomach” phenomenon. (Image: Getty/SrdjanPav)Source: Thalamic opioids from POMC satiety neurons switch on sugar appetite
Published online: 13 February 2025
DOI: 10.1126/science.adp1510
Authors: Marielle Minère, Hannah Wilhelms, Bojana Kuzmanovic et al.
