Researchers have revealed how eating stimulates brain’s endorphin and endogenous opioid system to signal pleasure and satisfaction.
The results obtained by researchers from Turku PET Centre have revealed that eating leads to widespread opioid release in the brain, likely signaling feelings of satiety and pleasure.
Eating a delicious pizza led to significant increase of pleasant feelings, whereas consumption of calorie-matched nutritional drink did not. However, both types of meals induced significant release of endogenous opioids in the brain.
Endogenous opioid system
Opioids associated with pleasure and euphoria. The study revealed that significant amount of endorphins released in the entire brain after eating the pizza and, surprisingly, even more released after the consumption of the tasteless nutritional drink.
The magnitude of the opioid release was independent of the pleasure associated with eating. According to the researchers, it is likely that the endogenous opioid system regulates both feelings of pleasure and satisfaction.
The opioid system regulates eating and appetite, and we have previously found that its dysfunctions are a hallmark of morbid obesity. The present results suggest that overeating may continuously overstimulate the opioid system, thus directly contributing to development of obesity.
These findings open new opportunities for treating overeating. Also the development of obesity, says Professor Lauri Nummenmaa from Turku PET Centre.
Its surprise that endorphins are released in the entire brain and the nutritional drink with larger impact. This creates a basis for future research and hopefully we will find ways to study and describe the development and predictors of addiction, obesity and eating disorders, says Researcher, M.D., PhD. Jetro Tuulari.
The study conducted using positron emission tomography (PET). Injected into participants with a radioactive compound binding to their brain’s opioid receptors.
Radioactivity in the brain measured three times with the PET camera. After a palatable meal (pizza), after a non-palatable meal (liquid meal) and after an overnight fast.