International media headlines reporting that heavy marijuana smokers have a six-fold risk of coming down with lung cancer are, predictably, a whole lot of hot air.
Had anyone in the mainstream media even bothered to read the study, which appears in the European Respiratory Journal, they would have stumbled across this nugget, “While cannabis smoking … was not associated with a significantly increased risk of lung cancer, those with the highest tertile of use had a significantly increased risk.”
So just how many subjects in the study (which, overall, assessed the risk in a measly 79 cases and 324 controls) qualified for the “highest tertile?” All of 14 cases and four controls! And, oh yeah, 70 of the 79 lung cancer cases also smoked tobacco.
Needless to say, prior population case control studies that have failed to find any relationship between cannabis use and cancer, such as this, this and this, do not receive nearly the same type of media attention. Go figure?
