"In the current study, we demonstrated that chronic cannabis smokers had relative visceral adiposity and adipose tissue insulin resistance but not hepatic steatosis, glucose insulin insensitivity, impaired pancreatic b-cell function, glucose intolerance, or dyslipidemia compared with age-, sex-, ethnicity-, and BMI-matched control individuals. Our study results suggest that chronic, daily cannabis use may have differential tissue-specific effects on insulin sensitivity, but these effects appear to have minimal impact on glucose or lipid metabolism."

Source

Muniyappa, Ranganath, MD, PhD, et al., "Metabolic Effects of Chronic Cannabis Smoking," Diabetes Care, e-published before print on March 25, 2013. DOI: 10.2337/dc12-2303. Clinical trial reg. no. NCT00428987, clinicaltrials.gov.
http://care.diabetesjournals.org...