Forget the Funyuns and drop the Doritos. New research out of Arctic Canada suggests that marijuana users, for some yet-to-be-understood reason, are slimmer and less at risk for diabetes than non-users.
A study by Quebec researchers found that among Inuit residents of Nunavik, the province's northernmost region, use of cannabis was correlated with lower body-mass-index measurements, lower body-fat percentages and less insulin resistance.
The study was published in the journal Obesity; results were presented last month at a circumpolar health conference in Finland. The study analyzed health data for 786 adults collected in the Nunavik Inuit Health Survey of 2004, making it one of the rare examinations of the subject in a North American aboriginal population. It included statistical controls for age, gender and other factors. In all, 57.4 percent of the survey subjects identified themselves as cannabis users. Those saying they use cannabis had an average BMI of 26.8, compared to an index of 28.6 for non-users; cannabis users had an average 25 percent body-fat reading, compared to an average 28 percent for non-users, according to the study.
People with BMI readings of 25 to 30 are generally considered overweight, and BMI readings above 30 are indicative of obesity.
The study results were a little surprising, said co-author Michel Lucas, an epidemiologist at CHU de Quebec Research Center and Montreal's Laval University. CHU is the French acronym for Centre hospitalier de l'Université.
"We expected some result on BMI or fat or insulin resistance," Lucas said. "We didn't know which one was going to be most important."
Past research, such as a recent French study of patients with HIV or hepatitis C infection, and a study published in 2013 in the American Journal of Medicine that evaluated health data collected from 2005 to 2010, has found a correlation between cannabis use and lowered insulin-resistance rates. Those studies added to other emerging evidence that cannabis, or components of it, could prove useful for treating or preventing diabetes. A 2009 Italian study, for example, suggested that cannabis is effective at treating diabetes-related pain, and a 2006 study in Israel found that components of cannabis reduced the incidence of diabetes in mice.
The Nunavik study results were subtly different. The study found that, according to biomarker evidence, insulin resistance was only a secondary result of cannabis use. The use of cannabis itself did not change the way people's bodies responded to insulin, but the lower BMI in the cannabis-user group led to lower rates of insulin resistance in that group, the study found.
Overall, the findings of the Nunavik study run contrary to stereotypes about marijuana smokers binging on fattening junk food, Lucas acknowledged. The remoteness of the region in question might have something to do with that, he said.
"I don't know if the 'munchies' that people are having may be kind of different there in these types of populations," he said.
What was not surprising, Lucas said, was the high rate of admitted cannabis use in the population. Consumer goods are expensive in Nunavik, largely because of the high costs of shipping items to such a remote place, and marijuana is lighter than alcohol or other consumables, he said.
Recreational use of marijuana is illegal in Canada – unlike in Alaska -- but the Nunavik residents in the study were not reluctant to talk about it, he said.
"There's no shame in smoking marijuana because it's so prevalent," he said. That is especially the case among the younger residents, who are more likely to use marijuana, he said.
Lucas said he and his colleagues hope to continue examining the subject in finer detail, with more information about frequency of cannabis use and a more specialized biomarker to revisit findings about insulin resistance.
The study does not endorse marijuana smoking as a wellness-promoting practice, despite the apparent correlation with lower BMI and insulin resistance.
"Smoking substances has a detrimental effect on your health," Lucas said.