Cannabis and Cancer Risk

You put your body in contact with combustion byproducts when you smoke anything. Cannabis smoke is not “cleaner” than tobacco smoke. What you want to know is if your cannabis use (and type of cannabis) is going to increase your cancer risk in the long term.

To give you an honest answer: the evidence is all over the map and depends heavily on how you are using cannabis, how often you are using cannabis, and whether or not you are also smoking tobacco.

Smoke Is the Problem (Not the Plant)

Chemically speaking, when you burn cannabis, you create similar toxic compounds and carcinogenic compounds as when you burn tobacco.

So from the perspective of “what are you breathing in?” smoke is a problem. However, it is a lot easier to prove the long term effects of smoking on cancer incidence in actual humans due to the fact that studies get messy quickly.

What Do Major Reviews Say About Cancer Risks?

There are two large reviews that summarize the current body of evidence regarding cancer risks associated with cannabis smoking.

• The National Academies Review (2017): There was moderate evidence of no statistically significant association between cannabis smoking and lung cancer. Similarly, there was moderate evidence of no statistically significant association between cannabis smoking and head and neck cancers.
• JAMA Network Open Systematic Review and Meta-Analysis (2019): There is insufficient evidence to establish a link between marijuana use and lung cancer. Part of the reason for this finding is related to the poor quality of the data and the lack of adequate methods to measure exposure.

Why This Is Such a Difficult Field to Study

There are several inherent challenges in studying cannabis and cancer:

• Confounding by tobacco use: Many people are dual users of cannabis and tobacco. Tobacco is a proven carcinogen and therefore confounds any findings relative to cannabis and cancer.
• Poor dose estimation: The dose of cannabis used in studies is rarely accurately quantified (e.g., “number of joints per year”) due to variability in size, potency and sharing practices, as well as the varying depths of inhalation.
• Different routes of administration lead to different levels of exposure: Smoking cannabis =/= THC vapes =/= consuming edible cannabis.
• Long latency periods for cancer: Cancers may take years or decades to develop, and changes in the legality of cannabis usage and reporting by individuals make long term follow-up studies challenging.

Different Modes of Administration Provide Different Types of Exposure: A Quick Comparison

Can Cannabis Give You Cancer?

Even if the plant itself is not the issue, what else is in the product could be. Poorly regulated distribution channels can contain pesticides residues, heavy metals or questionable vape additives. That’s one of the most pragmatic reasons to choose well-tested, clearly defined products from a reputable company.

Choose Quality You Trust

If you are using cannabis and you care about your long-term health, then the best thing you can do is to avoid sketchy products and only purchase products that are clearly labeled, consistent and made from responsible sources.

👉 Browse the Canna City catalog to compare quality cannabis products and select cleaner, more reliable options. If you’re looking to move away from smoke and toward more controlled formats, our weed edibles are clearly labeled and consistent.