Betsubara: Why We Can Eat Dessert Even After Overeating

Even after a filling meal, many people find they still have room for dessert. In Japan, this phenomenon is known as betsubara—literally “a separate stomach.” Although there is no anatomically separate compartment, the feeling that there is space for something sweet can be explained by a combination of physiological and psychological mechanisms, writes The Conversation.

The stomach is capable of stretching and adapting. During eating, a process called gastric accommodation occurs: the smooth muscles relax, creating additional volume without a significant increase in pressure. Light, sweet foods such as ice cream or mousse require minimal mechanical processing, allowing the stomach to expand further and creating the sensation of available space.

The brain also plays a role in the desire for dessert. There is what is known as hedonic hunger—the urge to eat for pleasure rather than due to physiological need. Sweet foods activate the dopamine reward system, increasing motivation and temporarily weakening satiety signals. In addition, the effect of sensory-specific satiety means that the brain gradually loses interest in foods already consumed; introducing a new flavor restores interest and stimulates appetite.

Sugar and carbohydrates leave the stomach quickly and require minimal digestion, which also contributes to the feeling that dessert is “easy” to eat. Satiety hormones, including cholecystokinin, GLP-1, and peptide YY, peak 20–40 minutes after a meal, so the decision to have dessert is often made before these signals take full effect.

Social and cultural factors matter as well. Dessert is traditionally associated with celebration, comfort, and reward, which heightens anticipation and desire. Studies show that people are more likely to consume dessert in social settings or on special occasions.

Thus, the ability to eat dessert after the main course is driven by a combination of physiological processes in the stomach and brain, along with psychological and cultural influences.

Follow NEWS.am Medicine on Facebook and Twitter