THURSDAY, Dec. 27, 2018 (HealthDay News) -- There may be a powerful reason why you can't resist that plate of brownies.
It turns out that eating causes the release of dopamine in your brain not once, but twice, German scientists report.
First, the feel-good hormone is unleashed as you eat. But the same thing happens again once that food hits your tummy, they said.
To come to that conclusion, researchers used a newly developed PET scan technique. Scans let them identify when dopamine is released, as well as the areas of the brain linked to dopamine release.
"While the first release occurred in brain regions associated with reward and sensory perception, the post-ingestive release involved additional regions related to higher cognitive functions," said senior study author Marc Tittgemeyer, from the Max Planck Institute for Metabolism Research in Cologne.
For the study, 12 volunteers received either a milkshake or a tasteless solution as PET scan data was recorded.
The researchers found that the desire for the milkshake was linked to the amount of dopamine released in particular brain areas as it was first tasted. But the higher the desire, the less dopamine was released after the milkshake was ingested.
The report was published Dec. 27 in the journal Cell Metabolism.
"On one hand, dopamine release mirrors our subjective desire to consume a food item. On the other hand, our desire seems to suppress gut-induced dopamine release," said lead author Heiko Backes, group leader for Multimodal Imaging of Brain Metabolism at the Institute.
Backes added that suppression of dopamine being released upon ingestion could cause overeating of desired foods.
"We continue to eat until sufficient dopamine was released," he said in a journal news release. But this hypothesis needs to be tested in further studies.
The U.S. Department of Health and Human Services has more on healthy eating.