Daily Marijuana Smoking Linked to Increased Risk of Head and Neck Cancers, Study Finds
Smoking marijuana daily for extended periods significantly raises the risk of developing head and neck cancers, according to a new study. The research, which analyzed insurance data, found that individuals with cannabis use disorder are at a heightened risk compared to those who do not use cannabis.
Dr. Niels Kokot, a clinical professor of otolaryngology-head and neck surgery at the Keck School of Medicine, University of Southern California, stated that the study revealed a strong association between cannabis use disorder and the likelihood of developing these cancers. Cannabis use disorder typically involves smoking about one joint per day over several years.
The study, published in JAMA Otolaryngology–Head & Neck Surgery, examined a database of 4 million electronic health records, identifying over 116,000 diagnoses of cannabis use disorder among individuals with head and neck cancers. The findings showed that those with this disorder were:
- 2.5 times more likely to develop oral cancer,
- Nearly 5 times more likely to develop oropharyngeal cancer (cancer of the soft palate, tonsils, and back of the throat),
- Over 8 times more likely to develop laryngeal cancer.
The study emphasized that smoke is a major contributing factor to this increased cancer risk, similar to the risks associated with tobacco use. Smoking tobacco is already known to double the risk of developing head and neck squamous cell carcinoma, which accounts for 90% of all head and neck cancers. The risk escalates with heavier tobacco use and is further exacerbated when combined with alcohol consumption.
However, the study did not find a significant link between occasional recreational marijuana use and the development of head and neck cancers.
The U.S. Centers for Disease Control and Prevention (CDC) defines cannabis use disorder as a condition diagnosed when a person exhibits two or more symptoms such as craving marijuana, developing tolerance to its effects, using more than intended, facing life problems due to its use, using it in high-risk situations, experiencing withdrawal, and being unable to quit.