Despite munchies, frequent cannabis users are leaner and less likely to get diabetes: study

Plants are shown at a California Street Cannabis Company location in San Francisco on March 20, 2023. (AP Photo/Jeff Chiu)

Despite the “munchies” being a common cannabis effect, frequent users are leaner and less likely to develop diabetes than people who don't use the drug. According to a new study that attempts to tackle this pot paradox, cannabis use in teenage years may alter how the body's fat cells work – and not necessarily for the better.

Study author Daniele Piomelli is a professor in the University of California, Irvine's anatomy and neurobiology department, and the director of the university's Center for the Study of Cannabis.

"All too often we think of cannabis only as a psychoactive drug," Piomelli said in a news release. "But, its effects extend well beyond the brain."

In the study, researchers gave adolescent mice low daily doses of THC, or tetrahydrocannabinol: the primary psychoactive ingredient in cannabis. When treatment was stopped in adulthood, they continued to evaluate the mice's metabolism and discovered that mice that had been exposed to THC as adolescents had reduced fat mass and increased lean mass than the control group. They were also more resistant to obesity and high blood sugar, had higher than average body temperatures, and were less able to use fuel from fat stores.

The study noted that several of these features are common to people who frequently use cannabis.

To understand why this is happening, the researchers analyzed the molecular changes caused by THC. Although the fat cells of the mice on THC looked normal under a microscope, they also unexpectedly produced large amounts of muscle protein, which is usually not found in fat, while their muscles had fewer of these proteins.

This unusual process, the researchers concluded, was interfering with the normal functioning of fat cells and their ability to store and release energy, meaning that they were less capable of utilizing stored nutrients for muscle activity. In addition to physical effects, this could also impact mental processes like attention, which require a steady flow of energy to the brain.

The study chose to focus on adolescence, because it a time of rapid physical development, and also when many regular users first try cannabis. The study defined "the munchies" as "the stimulation of hedonic high-calorie eating" and one "of cannabis’ most iconic effects."

The study was published on June 1 in the peer-reviewed journal Cell Metabolism.

"[Cannabis'] main constituent, THC, mimics a group of chemical messengers called endocannabinoids, which regulate important functions throughout the body," Piomelli explained. "Our results show that interfering with endocannabinoid signaling during adolescence disrupts adipose organ function in a permanent way, with potentially far-reaching consequences on physical and mental health."