Research in mice suggests that the brain region responsible for feelings of fullness is also linked to sugar cravings. The study, led by Henning Fenselau at the Max Planck Institute for Metabolism Research in Germany, found that neurons that regulate appetite and satiety are also involved in triggering sugar cravings.
The researchers used a fluorescent solution to track the activity of these neurons in the brain, which is regulated by naturally occurring opioids. They discovered that when mice were presented with their usual food, the neurons didn’t show much activity. However, when they were offered a dessert, the neuronal activity quadrupled, indicating a strong link between sugar cravings and the brain’s fullness signals.
The study used an optogenetics technique to switch cells on and off with light, which confirmed that inhibiting signals from these neurons reduced sugar consumption by 40 per cent. The researchers propose that this pathway may have evolved because sugar is easily converted into energy, much like refueling a gas tank.
While the study suggests a potential new target for obesity treatments, Fenselau acknowledges that hunger and cravings are complex and influenced by multiple pathways in the brain.
Source: https://www.newscientist.com/article/2468346-why-we-may-crave-dessert-even-when-we-are-full-from-dinner