Cancer ResearchHeavy Marijuana Smoking Linked to Lung and Head and Neck Cancer Risk
Heavy marijuana smoking may substantially raise the risk of lung cancer and head and neck cancers, according to researchers at USC's Keck School of Medicine. One study found daily marijuana users were 3.5 to 5 times more likely to develop cancers of the mouth, throat, and larynx compared to non-users. Heavy smokers also showed elevated risk for both small cell and non-small cell lung cancer. Scientists believe chronic inflammation from inhaled smoke — which shares many carcinogenic chemicals with tobacco — is a key driver. The dose-response relationship remains unclear, and occasional use may carry minimal risk. Edibles have not been linked to lung cancer so far, though their effects on other cancers are still under investigation.
