Researchers at the University of Oregon have shown that worms, much like humans, exhibit increased appetite after exposure to cannabis compounds. The findings point to a very old, perhaps universal, role for the endocannabinoid system across living beings. This work appears in current biology.
One of cannabis’s most recognized effects is a marked rise in hunger. In a new study, scientists worked with the nematode Caenorhabditis elegans. They administered high levels of anandamide, a compound present in cannabis, and observed how the worms responded to different food sources. These roundworms typically feed on bacteria found on decaying plant matter.
To test food preference, the researchers offered five varieties of bacteria to the worms. These bacteria varied in how quickly they promoted nematode growth after consumption. The team found that after being exposed to anandamide, the worms rapidly consumed the growth-promoting bacteria and showed little interest in the others. The results indicate that anandamide not only shifts worms toward growth-enhancing food but also accelerates their intake of such food.
In a follow-up step, the scientists replaced the worms’ anandamide receptor with one from humans and repeated the same experiment. The outcome remained consistent, underscoring the functional compatibility across species.
Experts in the study noted that cannabinoid receptors appear interchangeable between worms and humans, highlighting a shared influence of cannabinoids on these organisms despite roughly 500 million years of evolution separating them.
The researchers suggest that the endocannabinoid system likely serves similar roles in a broad range of animal species. These roles include regulating food intake and, in particular, the aspect known as hedonic nutrition, where craving targets tasty, high-calorie foods rather than nutritional necessity alone.