The fact that our brain’s response to food relies on a dopamine release system is not a recent discovery; however, researchers at the Max Planck Institute for Metabolism Research in Germany used a newly developed positron emission tomography (PET) technique to not only find that two peaks of dopamine are actually released, but were also able to identify the specific brain regions associated with them.
According to a report in Cell Metabolism, food induced both “an immediate and post-ingestive dopamine release,” meaning that they observed a peak in dopamine both when food was initially ingested, and then again approximately 15-20 minutes later after the stomach registered the presence of food.
The team also took this opportunity to examine the “complex interplay between orosensory and nutritive signals.” During the study they gave 12 men, all of whom had fasted overnight before the test, either a flavored milkshake or a nutritionally similar tasteless drink. Those that consumed the flavored milkshake experienced the two spikes mentioned above, while those with the flavorless drink only produced the second response.
When looking at the areas of the brain that reacted during this test, they also “unexpectedly found a strong negative correlation between and the places that responded to receiving the food,” Stephen Luntzwrites. “The paper speculates a high desire to eat inhibits the release of dopamine in the putamen, located in the forebrain region. This could indicate that the more you want food, the less effective the message is that you’ve had enough, encouraging over-consumption, particularly of the most desired foods.”
While additional hypotheses uncovered by this study will need to be examined in further tests, it’s hoped that gaining further understanding about how our brains respond to food will help us to better tackle both common eating disorders like anorexia, as well as the growing obesity epidemic.