Marijuana use may improve insulin resistance in adults with obesity
Fasting insulin levels may be reduced by more than half in adults with obesity who use marijuana compared with those who do not, according to findings published in the Journal of Diabetes.
“Findings are important in the current social context of regularization of recreational marijuana use. Also, previous studies account for neither the duration of marijuana exposure nor the time elapsed since last use,” Gerard Ngueta, PhD, MSc, MPH, a postdoctoral research associate in the faculty of pharmacy at Laval University in Quebec, Canada, told Endocrine Today. “The findings emphasize the fact that the apparent association of marijuana with fat mass should be deeply investigated at cell and mechanistic levels.”
Ngueta and Ruth Ndjaboué, MA, MPH, PhD, of the department of social and preventive medicine of the faculty of medicine at Laval University, conducted a cross-sectional observational study using data from 129,509 adults (mean age, 37.8 years; 50.3% women) who participated in the National Health and Nutrition Examination Survey between 2009 and 2016. The data included answers to health questionnaires, which helped establish marijuana use patterns, and blood samples, which allowed the researchers to identify fasting insulin and fasting blood glucose levels to determine readings for homeostasis model assessment for insulin resistance (HOMA-IR).
Participants with obesity as defined by a BMI of at least 30 kg/m2 made up 32.6% of the study population. When compared with participants in this group who had a history of marijuana use, there were reductions of 52% (adjusted ratio of means [ARM] = 0.48; 95% CI, 0.29-0.81) and 58% (ARM = 0.42; 95% CI, 0.24-0.72) in fasting insulin levels and HOMA-IR, respectively, for those who reported currently using marijuana at least once but fewer than four times per month.
According to the researchers, if participants with obesity had been using marijuana at least eight times per month but had quit, their fasting insulin levels and HOMA-IR were reduced by between 35% and 47% vs. those with no prior marijuana use depending on how long ago they had stopped use.
Compared with those with obesity who did not use marijuana at any point, fasting insulin levels were decreased by 41% (ARM = 0.59; 95% CI, 0.42-0.82) and HOMA-IR was reduced by 42% (ARM = 0.58; 95% CI, 0.4-0.84) among those with obesity who had not used marijuana in at least a decade but previously used the drug fewer than four times per month. Similarly, respective reductions of 42% (ARM = 0.58; 95% CI, 0.38-0.9) and 41% (ARM = 0.59; 95% CI, 0.37-0.95) in fasting insulin and HOMA-IR were noted for those with obesity who had quit during the last decade after using marijuana fewer than four times per month vs. those with no previous use.
The researchers further observed that fasting insulin levels and HOMA-IR were 38% lower for those with obesity who previously used marijuana between four and seven times per month but had not used the drug for at least a decade compared with those who reported no marijuana use at any point. In addition, participants with obesity who stopped marijuana use of between four and seven times per month during the previous year experienced declines of 39% (ARM = 0.61; 95% CI, 0.41-0.92) and 41% (ARM = 0.59; 95% CI, 0.37-0.95) in fasting insulin and HOMA-IR, respectively, compared with their non-marijuana-using counterparts.
When examining those with a BMI of less than 25 kg/m2 or between 25 kg/m2 and 30 kg/m2, the researchers noted that there were fewer associations of consequence between marijuana use and insulin levels compared with the participants with obesity.
“At this step, I feel that early conclusions about clinical implications may be inappropriate. However, our findings suggest that medical use of marijuana may be useful to prevent insulin resistance in obese individuals,” Ngueta said. “Surely, further investigations are needed to confirm such a hypothesis.” – by Phil Neuffer
Gerard Ngueta, PhD, MSc, MPH, can be reached at firstname.lastname@example.org.
Disclosures: The authors report no relevant financial disclosures.