Most of us will know this experience well. Despite eating a satisfying meal and feeling full, the temptation of a sugary dessert is just too great to resist. But how is it that we can find room for a sugary treat even when we already feel full? Science has the answer.
Those who simplify their sweet tooth down to a simple lack of will power will find comfort in the fact that our insatiable urge to eat sugar is more about survival than greed, and scientists in Germany have even coined the phenomenon as a case of “dessert stomach.” In a newly published study, researchers at the Max Planck Institute in Cologne, Germany, recently discovered that the brain creates cravings for sugar even when our bellies are bursting at the seams. From an evolutionary perspective, this makes perfect sense.
Why Do We Eat Sugary Foods Even When We Feel Full?
First studying mice, the scientists observed that completely satiated subjects still devoured desserts. Apparently, neurons in the brain become active once given access to sugar, and this activates the appetite. Not only were the usual molecules released in order to encourage the mice to feel full, but opiate receptors also triggered the mice to create ß-endorphin, providing a feeling of reward. It is this endorphin response that is thought to encourage us to eat beyond fullness. When humans volunteered to have their brans scanned after ingesting a sugar solution through a tube, they found the same response in us as they did with the mice.
“From an evolutionary perspective, this makes sense,” explains Henning Fenselau, the research group leader at the Max Planck Institute for Metabolism Research and head of the study. “Sugar is rare in nature, but provides quick energy. The brain is programmed to control the intake of sugar whenever it is available.”
There’s no question that abstaining from sugar is a sticky subject. The experts found that even those who perceived the presence of sugar, without actually ingesting it, were triggered to eat more. Still, experts believe that while there is still a way to go, the concept of blocking ß-endorphin requires further attention because it does not appear to obstruct regular appetite. In hungry mice that weren’t not full, blocking the endorphin did not stop them from eating, but it did derail their dessert stomach desires.
“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, we need to investigate this further,”
So, next time you find yourself seduced by sugar, don’t be too hard on yourself, but if you just finished an adequate meal, ask yourself if you really need that additional energy, or if you just have a case of dessert stomach.
