#8 – Consuming Cannabis Causes Cancer
Myth: Consuming Cannabis causes cancer.
Truth: A number of studies have established that even long-term use of cannabis (via smoking) in humans is not associated with elevated cancer risks, including tobacco-related cancers or with cancer affecting the bowels, lungs, skin, prostate, breasts or cervix. A 2009 population-based case-control study found that moderate marijuana smoking over a 20 year period was associated with reduced risk of head and neck cancer (Liang et al).
It seems the only thing the vast majority of research studies have been able to conclude is that heavy smoking of cannabis with tobacco increases the risk of developing cancers that are associated with smoking normal cigarettes e.g. lung and upper aerodigestive tract cancer.