For some time it has been acknowledged that the cannabiniods in marijuana smoke have potential antitumor properties. Now an epidemiological study conducted at Brown University has found that the practice of long term marijuana smoking reduces the risk of developing head and neck cancer (HNSCC). The researches discovered that “20 years of marijuana use was associated with a significantly reduced risk of HNSCC (OR10-<20 yrs vs never users=0.38, 95% CI=0.22–0.67). Among marijuana users moderate weekly use was associated with reduced risk (OR0.5-<1.5 times vs. <0.5 time =0.52, 95% CI=0.32–0.85). The magnitude of reduced risk was more pronounced for those who started use at an older age (OR15-<20 yrs old versus never users =0.53, 95% CI=0.30–0.95; OR>=20 yrs old versus never users =0.39, 95% CI=0.17–0.90, ptrend <0.001). These inverse associations did not depend on HPV 16 antibody status.” They concluded that “our study suggests that moderate marijuana use is associated with reduced risk of HNSCC.” However, it should be noted that when cannabis was combined with tobacco use and alcohol consumption the risk increased.

Hat Tip to Ian Goddard

Cross posted on The Trebach Report