On the surface, it stands to reason that people who smoke cannabis could possibly face similar elevated risks for head and throat cancers as do those who smoke tobacco, and/or drink alcohol. Both alcohol and tobacco use carry significantly higher risks for such cancers.
In 1999, a highly – publicised study indicated that cannabis users might face some elevated risk of head and neck cancers, as is the case with consumers of tobacco and alcohol. However, even the researchers from that study cautioned against making too much of their results and called for further study.
Two recent studies appear to contradict that, suggesting that cannabis users face no increased risk of head and neck cancers, and may even enjoy a measure of protection. Results show that moderate cannabis users actually appear to have a reduced risk level for head and neck cancers compared to control cases. However, due of the limited power and length of use studied, a small or longer-term effect cannot be ruled out.
Both of these studies support a growing body of data that indicate that cannabinoids have potential anti-tumour and anti-cancer properties. Clearly, further examination is required!