This article exists as part of the online archive for HuffPost Canada, which closed in 2021.

Brain Cells Cause Munchies After Smoking Pot, Study Finds

Hey Pot Smokers, Your Brain Is Responsible For The Munchies
Open Image Modal
yalcinsonat1 via Getty Images
heap of potato crisps on white background

People who empty the refrigerator after smoking cannabis can blame their cravings on brain cells that normally suppress appetite, a study published on Wednesday said.

Researchers using genetically-modified mice pinpointed circuitry in the hypothalamus used by the active ingredient in cannabis to cause the "munchies."

"We were able to see what drives the hunger brought about by cannabis and how that same mechanism that normally turns off feeding becomes a driver of eating," said Tamas Horvath of Yale University, who led the unusual study.

The active compounds, cannabinoids, work on a select group of nerve cells called pro-opiomelanocortin (POMC) neurons, his team found.

POMC cells have until now been considered the big stoppers of over-eating, for they send out signals to say when satiety has been reached.

But to the scientists' surprise, the cells' activity flipped over when affected by cannabinoids.

Instead of a sending out a chemical signal that said in essence "I'm full," they sent out a neurotransmitter called endorphins, which are known appetite-boosters.

"It's like pressing a car's brakes and accelerating instead," Horvath said in a press release.

"We were surprised to find that the neurons we thought were responsible for shutting down eating were suddenly being activated and promoting hunger, even when you are full. It fools the brain's central feeding system."

Cannabinoids have also been found to affect other areas of the brain that touch on appetite, enhancing perceptions of smell and taste.

If replicated among humans, the findings could help to treat people with eating problems, such as cancer patients who lose their appetite during treatment.

The study appears in the journal Nature.


Cannabis laws around the world
The Netherlands(01 of 06)
Open Image Modal
Production of cannabis is still illegal, but the country's famous liberal approach has seen its famous coffee shops become a tourist attraction. (credit: PA)
Switzerland(02 of 06)
Open Image Modal
In October, the Swiss decriminalised marijuana. Possession does not go on a person's criminal record. (credit: Getty Images)
Spain(03 of 06)
Open Image Modal
Use of cannabis is not illegal in private. (credit: Getty Images)
United States(04 of 06)
Open Image Modal
Recreational use of small amounts of cannabis has has been legalised in Colorado and Washington. 18 other states allow use for medical reasons. (credit: Getty Images)
Portugal(05 of 06)
Open Image Modal
In 2001 it became the first country in Europe to scrap criminal penalties for personal possession of drugs including cannabis. (credit: Getty Images)
North Korea(06 of 06)
Open Image Modal
Not what you might expect. According to reports, "marijuana is reportedly not considered a drug" under Kim Jong Un's dictatorship. (credit: AP)
-- This article exists as part of the online archive for HuffPost Canada. Certain site features have been disabled. If you have questions or concerns, please check our FAQ or contact