3 Effects of Smoking Marijuana
Marijuana Use Linked to Increased Risk of Head and Neck Cancers
Recent research reveals a significant connection between long-term daily marijuana use and an elevated risk of head and neck cancers. An extensive study analyzing millions of medical records found that individuals with cannabis use disorder—marked by symptoms such as cravings, tolerance, and withdrawal—are three to five times more likely to develop these cancers compared to non-users.
Cannabis use disorder is diagnosed when a person exhibits at least two of the following symptoms defined by the US Centers for Disease Control and Prevention: intense cravings, diminished effects over time, excessive use, continued use despite negative consequences, and difficulty quitting.
Dr. Niels Kokot, a professor of clinical otolaryngology-head and neck surgery at the Keck School of Medicine, University of Southern California, explains that cannabis users, especially those with a cannabis use disorder, are at a notably higher risk of developing head and neck cancers. “Although our study didn’t specify the methods of cannabis consumption, smoking is the most common method, and the risks we observed are likely related to smoked cannabis.”
Survival rates for head and neck cancers vary; about 69% of people diagnosed with oral or throat cancer survive for five years or more, but this rate drops to 14% if the cancer spreads. Similarly, around 61% of individuals with laryngeal cancer survive for five years, a figure that falls to 16% with metastasis.
Dr. Joseph Califano, Chair of Head and Neck Surgery at the University of California, San Diego, noted that the study’s use of a vast dataset provides substantial power and precision. “On average, individuals with cannabis use disorder smoke approximately one joint daily for several years or more,” Califano said. He coauthored an editorial in *JAMA Otolaryngology-Head & Neck Surgery* alongside the study.
However, it is important to note that the study did not establish a link between occasional recreational marijuana use and head and neck cancers.
