Background
In preclinical animal studies, evidence links cannabis smoking (CS) with hyperphagia, obesity, and insulin resistance. Nonetheless, in humans, CS might protect against type 2 diabetes mellitus (DM). Here, we offer epidemiological estimates from eight independent replications from (1) the National Health and Nutrition Examination Surveys, and (2) the National Surveys on Drug Use and Health (2005-12).
Methods
For each national survey participant, computer-assisted self-interviews assess CS and physician-diagnosed DM; NHANES provides additional biomarker values and a composite DM diagnosis. Regression analyses produce estimates of CS-DM associations. Meta-analyses summarize the replication estimates.
Results
Recently active CS and DM are inversely associated. The meta-analytic summary odds ratio is 0.7 (95% CI = 0.6, 0.8).
Conclusions
Current evidence is too weak for causal inference, but there now is a more stable evidence base for new lines of clinical translational research on a possibly protective (or spurious) CS-DM association suggested in prior research.
