Scientists Have Figured Out Why Pot Causes the Munchies


Feeling guilty after a case of the munchies drove you to eat an entire sleeve of Red Velvet Oreos? A new study might let you off the hook.

Researchers at Yale University have discovered that the active ingredient in marijuana prohibits the neurons responsible for restricting appetite from working, which means that after smoking up, the neurons stop transmitting signals that tell you when you're supposed to be full. What happens next is the stereotypical uncontrollable caloric intake of someone who's passed one too many dutchies.

Tamas Horvath, the lead author of the study, said in an announcement that the brain is essentially tricked by marijuana, which leads to the munchies.

"It fools the brain's central feeding system," Horvath said, according to the Washington Post. "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."

Brennan Linsley/AP

The study: Horvath and his team of researchers focused on the brain's receptors to which cannabinoids attach and activate. Instead of discovering that those cells send out signals suppressing the appetite, they discovered that the cannabinoid receptors released endorphins that encourage eating.

"By observing how the appetite center of the brain responds to marijuana, 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 Horvath, per Science Daily. It doesn't trick the brain into eating doctor-approved foods, like kale and carrots. Rather, the brain mechanisms urge you to crave calorie-heavy and salty foods, like Taco Bell, and rich sweets. That likely happens because weed enhances those flavors "by acting directly on taste receptors, rather than just in the brain," notes Smithsonian.

Bottom line: "Marijuana fools the brain's feeding system," Hovrath told Reuters.

It remains unclear how strong this reaction is happening in people compared to mice. "Obviously, this is a very primitive mechanism that's likely to be the same in humans," he told the Washington Post. "Nevertheless, there needs to be confirmation of that."

It's good news for Taco Bell — and better news for cancer patients. People undergoing chemotherapy, radiation or other medical treatments can often lose their appetites, leading to so-called "wasting disease" that makes recovery even more difficult. By offering conclusive proof that marijuana (or, at least, the THC contained therein) encourages eating in those who aren't hungry, the study gives ammunition to activists pushing for legalized medical marijuana to help treat a fleet of illnesses, from inflammatory bowel disease to Crohn's disease.