We’ve all been there: You’ve just eaten a big dinner, but you find yourself craving a little sweet treat. Is there a biological explanation for why we always want to leave room for dessert?
A team from the Max Planck Institute for Metabolism Research says yes, there is actually science behind the “dessert stomach,” and it all starts in the brain.
Sugar on the Brain
In their initial study, researchers used mice to investigate the brain’s reaction to sugar. More specifically, they focused on why sugar seems to cause a particular response in the brain, especially when stomachs are already full.
Scientists ran a series of tests on the mice to help find an answer. They first allowed the mice to eat until they were full and then presented them with access to either a sugar solution, fatty foods, or their normal meal. The team also ran similar tests on hungry mice, presenting them with the same food options and monitored the neurological reactions that happened in their brains — the results were surprising.
A Sweet Response
A group of nerve cells, known as POMC neurons, are responsible for many things. Mainly, they are key to the regulation of energy and metabolism. This regulation occurs through the release of signals to the rest of the body, like telling us when we are full.
This group of nerve cells also signals the release of one of the body’s naturally-occurring opiates, which often occurs after eating sugar.
Once the mice were given access to sugar, the POMC neurons lit up and began to signal these opioid pathways. Interestingly, fatty or normal food did not trigger the same response, and the mice who ate sugar when hungry also exhibited no neurological effects.
For the full mice, however, even just the sight of the sugary substance caused the neurons to activate and flood their system with endorphins.
There was even a neurological reaction in mice who had never eaten sugar before. Once the mice got their first taste of dessert, the endorphins were immediately released, and the cravings strengthened after subsequent sugar consumption.
Read More: Sugar’s Bad Rep Is Worse Than The Sweet Stuff Itself
What Happens to Humans?
After running the initial rounds of testing on mice, the research team moved on to human volunteers to see if our brains had a similar reaction.
Once they had eaten until they were full, volunteers were given a sugar solution through a tube while scientists monitored their neuron activity through brain scans. It was revealed that the same area of the brain showed responses in humans.
Like in a mouse’s brain, human brains also have opiate receptors close to the neurons that signal fullness. This leaves one feeling content and rewarded after finally giving in to those post-meal sugar cravings, even if moments before, the same neurons were telling us to stop eating. For Henning Fenselau, the research group leader, this response likely has evolutionary roots.
“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,” Fenselau said in a press release.
Can We Overcome Dessert Stomach?
These findings are incredibly important for the ongoing scientific concern with treating obesity.
During the mice study, researchers discovered that if they stopped the signal and blocked the opioid pathway in the brain, the mice no longer were interested in eating sugar when full or otherwise. Although more research is needed, this suggests that a combination of pathway-blocking drugs and appetite suppressant injections could have revolutionary potential for those suffering from obesity and overeating disorders.
This article is not offering medical advice and should be used for informational purposes only.
Read More: Here's How Ozempic Actually Works for Weight Loss
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:
Max Planck Institute for Metabolism Research. Dessert stomach emerges in the brain
As the marketing coordinator at Discover Magazine, Stephanie Edwards interacts with readers across Discover's social media channels and writes digital content. Offline, she is a contract lecturer in English & Cultural Studies at Lakehead University, teaching courses on everything from professional communication to Taylor Swift, and received her graduate degrees in the same department from McMaster University. You can find more of her science writing in Lab Manager and her short fiction in anthologies and literary magazine across the horror genre.
