The finding runs contrary to the belief that marijuana users who get “the munchies” will ultimately gain more weight.
“Over a three-year period, all participants showed a weight increase, but interestingly, those who used marijuana had less of an increase compared to those that never used,” says Omayma Alshaarawy, assistant professor of family medicine at Michigan State University and lead author of the paper in the International Journal of Epidemiology. “Our study builds on mounting evidence that this opposite effect occurs.”
The results also suggest that new and persistent users are less likely to be overweight or obese, overall.
“We found that users, even those who just started, were more likely to be at a normal, healthier weight and stay at that weight,” Alshaarawy says. “Only 15 percent of persistent users were considered obese compared to 20 percent of non-users.”
Researchers used National Epidemiologic Survey of Alcohol and Related Conditions data and looked at the Body Mass Index, or BMI, of 33,000 participants, ages 18 and older, then compared the numbers.
While the actual weight difference among users and non-users was modest, around two pounds for a 5-foot-7-inch participant weighing about 200 pounds at the start of the study, the variance was prevalent among the entire sample size.
“An average 2-pound difference doesn’t seem like much, but we found it in more than 30,000 people with all different kinds of behaviors and still got this result,” Alshaarawy says.
So, what is it about marijuana that seems to affect weight? Alshaarawy indicated it’s still relatively unknown but points to several factors possible factors.
“It could be something that’s more behavioral like someone becoming more conscious of their food intake as they worry about the munchies after cannabis use and gaining weight,” she says. “Or it could be the cannabis use itself, which can modify how certain cells, or receptors, respond in the body and can ultimately affect weight gain. More research needs to be done.”
But, people shouldn’t use marijuana as a diet aid, Alshaarawy cautions.
“There’s too many health concerns around cannabis that far outweigh the potential positive, yet modest, effects it has on weight gain,” she says. “People shouldn’t consider it as a way to maintain or even lose weight.”
The National Institutes of Health funded the work.
This article was re-published under the Attribution 4.0 International license via Futurity.