Podhead? Marijuana may up pre-diabetes risk

Potheads! You may want to avoid smoking up weed as a study has shown that current and former users of marijuana are more likely to have prediabetes, the state of poor blood sugar control that can progress to type 2 diabetes, than never users of cannabis.

However, the research, led by University of Minnesota School of Public Health's Mike Bancks, failed to establish a direct link between marijuana use and type 2 diabetes.

Marijuana is the most frequently used illicit drug in America (and is estimated to be so globally), with an estimated 18.9 million people aged 12 or older in the USA identifying as current users in 2012.

In this new study, the authors investigated the association between self-reported marijuana use and concurrent and incident prediabetes and full blown type 2 diabetes, considering both quantity used and status of current use.

They also aimed to examine the role of body mass index (BMI) and waist circumference as potential confounding and/or mediating factors to these associations. Lastly, given the varying diabetes risk profiles by race and gender, they looked at the effects of sex and race on the associations.

The authors said that it is unclear how marijuana use could place an individual at increased risk for prediabetes yet not diabetes, but it could be because individuals excluded from the study (due to missing information on important factors) generally had higher levels of marijuana use and greater potential for development of diabetes, or that marijuana may have a greater effect on blood sugar control in the prediabetic range than for full blown type 2 diabetes, when other traditional diabetes risk factor levels are exceedingly less favourable.

The authors concluded that marijuana use by status or lifetime frequency was not associated with incidence or presence of diabetes after adjustment for potential confounding factors.

They added that however, marijuana use was associated with the development and prevalence of prediabetes after adjustment. Specifically, occurrence of prediabetes in middle adulthood was significantly elevated for individuals who reported using marijuana in excess of 100 times by young adulthood.

These results contrast with those previously reported on marijuana use and metabolic health. Future studies should look to objectively measure mode and quantity of marijuana use in relation to prospective metabolic health, they noted.

The study is published in Diabetologia.