Light Marijuana Use Appears Protective against Diabetes

Article excerpt

DENVER -- Marijuana use may be associated with a markedly decreased risk of diabetes.

A provocative new analysis of data from the Third National Health and Nutrition Examination Survey (NHANES III) indicates marijuana users had 66% lower odds of having diabetes after adjustment for numerous potential confounding factors, Dr. Magda Sha-heen reported at the meeting.

This robust observed benefit has a biologically plausible mechanism, she noted.

In addition to defects in pancreatic beta-cell function and insulin sensitivity, the pathogenesis of diabetes is thought to involve systemic inflammation. Marijuana contains bioactive cannabinoids that have been shown to have an anti-inflammatory effect. This was borne out in the NHANES III analysis, where the prevalence of an elevated C-reactive protein level in excess of 0.5 mg/dL was significantly higher in nonusers of marijuana, at 18.9%, than in past users, with a 13% prevalence of elevated CRP, current light users (16%), or current heavy users of the illicit drug (9%), according to Dr. Shaheen of Charles R. Drew University of Medicine and Science, Los Angeles.

The study population consisted of 10,896 NHANES III participants aged 20-59 years; they constituted a statistically representative sample of the broader U.S. civilian population in 1988-1994, when the survey was conducted. The majority of subjects - 55% - reported never having used marijuana. Another 37% were past users, meaning they hadn't used marijuana during the previous month. The 6% of subjects who reported currently using the drug 1-4 days per month were categorized as current light users, while 3.3% of subjects were current heavier users.

The age-adjusted prevalence of diabetes in this cross-sectional study was 4% in nonusers and significantly lower at 3% in marijuana users. Current and past users were significantly younger, had a lower body mass index, were more physically active, and were more likely to smoke cigarettes, drink alcohol, and use cocaine than were nonusers. They were more likely to have an HDL level greater than 40 mg/dL and had lower mean total cholesterol, LDL, and triglyceride levels.

In a multiple logistic regression analysis adjusted for sociodemographic factors, comorbid conditions, laboratory values, and inflammatory markers, marijuana users had a 66% lower likelihood of having diabetes. …