Here's why your brain says there's always room for dessert, even when you’re totally stuffed
Humans are hardwired for sweets, even after a big meal.

Three teenage girls enjoying some cake.
Have you ever felt like you can hardly stand after having a big dinner at a restaurant, but when the dessert menu is dropped on the table, your stomach miraculously finds a way to accommodate another 800 calories of cheesecake? Does that mean you weren’t completely full, or your stomach can always find room for dessert? According to a recent study out of Germany, we’re programmed to find room for dessert, even when legitimately full.
The Max Planck Institute for Metabolism Research, led by Henning Fenselau, PhD, performed a study on mice after being confused by what they call “dessert stomach” or the strange way we have an appetite for sugary foods when we have zero interest in another bite of our dinner. The researchers found that after eating a meal, a paradoxical thing happens: the same neurons that trigger us to feel satisfied also create a desire for sugary foods simultaneously.
A couple enjoying some cheesecake.via Canva/Photos
To understand why this surprising effect happens with our appetites, the researchers gathered a hungry group of mice and fed them chow for 90 minutes. After the mice were satisfied, the scientists offered them another 30-minute period where they were given more chow or a substance high in sugar. The mice given a second helping of chow would take a little nibble, but if they were given a meal high in sugar, they would increase their caloric intake sixfold. For humans, this is like enjoying a filling club sandwich with soup and salad, then knocking back a nine-scoop sundae with whipped cream, nuts, and a cherry. “This vigorous stimulation of consumption of the high sugar–containing food was consistent across all mice,” the researchers wrote.
Is dessert stomach real?
The secret to “dessert stomach” lies in a group of nerve cells called pro-opiomelanocortin (POMC). When the mice were full of chow, these neurons fired off signals that they were satiated. At the same time, it also triggers the release of ß-endorphin, one of the body’s opiates that creates a feeling of reward that causes the mice to continue to consume sugar even after they are full.
It’s also worth noting that the opiate was released in mice that had never even tasted sugar before, showing they are hard-wired to consume sugar every chance they get. “From an evolutionary perspective, this makes sense: sugar is rare in nature but provides quick energy,” Fenselau said. “The brain is programmed to control the intake of sugar whenever it is available.”
'Dessert stomach': when you COULDN'T POSSIBLY EAT ANY- oh ok yeah maybe we'll split the cheesecake https://t.co/nKUJbnU7bN
— Merriam-Webster (@MerriamWebster) November 9, 2018
Scientists believe humans have a strong drive to consume sugar because its energy allows them to stave off starvation, giving them a greater chance to reproduce. However, fruit is often found high up in trees, so the primates would need a strong drive to climb the tree to get it. The amount of sugar provided by these fruits was relatively small, so there were no adverse health impacts from eating whatever sugar they could get their hands on. But in 2025, at a time when sugar is plentiful, this drive is a big reason for the obesity epidemic in developed countries.
The good news about the study is that the next time you eat a big meal and still crave a hunk of cake even after you are full, it’s not because you prioritized dessert over your nutritious meal. It’s because, over thousands of years of evolution, your mind has found a way to trick you into eating all the sugar you can, even when you don’t have any space left for anything else.