Worms Get the Munchies, Scientists Discover In Cannabis Experiment

If you get hungry when you’re high (AKA the munchies), you have something in common with worms, according to new research. 

Getting intense food cravings is just one of the many effects of cannabis. But apparently, it’s not just humans that get the munchies. A study published on Thursday (4/20, naturally) in Current Biology by a group of researchers at the University of Oregon demonstrates that a common model organism, nematode worms (Caenorhabditis elegans or C. elegans) also activates their appetite.

Tetrahydrocannabinol, or THC, is the primary psychoactive component in weed, the compound responsible for that “high” feeling. THC binds to special cannabinoid receptors in the body (humans are basically hardwired to respond to these compounds because they already exist in the body). These receptors are believed to mediate a number of different behaviors, including eating––which explains why stoned humans are so drawn to high caloric foods. 

A few years ago, a group of researchers at the University of Toledo discovered that C. elegans have a similar system of cannabinoid compounds and receptors. Around the same time, cannabis had just been legalized in Oregon.

 “It was in the air, literally,” Shawn Lockery, a professor of biology at Oregon and one of the paper’s authors, told Motherboard. 

Although his background is in physiology, Lockery’s research group had been conducting a number of value-based decision making experiments with worms. “We got really good at doing food choice assays, where we were pitting high-quality food against low-quality food,” he explained. They decided to take advantage of the newly legal status of cannabis and have some fun with it. 

“It was really a form of scientific play,” Lockery said. The group soaked the worms in a cannabinoid-containing liquid, and then put them through food choice assays––that is, made them choose between low- and high-quality foods to see if they indeed had the munchies.

Though as Lockery explained, they had to be a bit more scientific with their descriptions.

“You never see ‘the munchies’ in the body of a paper,” he told me. “The technical term for that extra craving for highly caloric fatty food is called ‘hedonic feeding.’” 

And crave they did. When exposed to an endocannabinoid—meaning a cannabinoid that naturally arises in the body—they tended to gravitate towards their “favorite food” and would eat more of it.

“Now we know there’s this very human-like behavior, getting the munchies, and it’s regulated by exactly the same protein signaling system,” Lockery said. As he explained, those systems are so similar that when they took out the worm gene and put in a human gene, it worked the same way.

“This means we have a humanized worm for cannabinoid signaling, and now we have a test platform for doing genetic research to identify other components of the cannabinoid signaling system,” he said. 

To Lockery, these findings not only could help inform drug development, but also help us better understand our place in the animal universe.”

As for what’s next? Lockery and his team have already started experiments on another drug newly legal in Oregon: psychedelics. 

“Psychedelics operate through a particular serotonin receptor and there’s a similar receptor in C. elegans,” he said. “This is just early days but we’re doing behavioral assays to see if psychedelics affect behavior.”