A working group of scientists of several universities in the USA (universities of Rhode Island, Massachusetts, Louisiana, and Minnesota) investigated the effects of cannabis use on the development of a certain head and neck cancer (head and neck squamous cell carcinoma).

Information of cannabis use by 434 patients was compared with data of 547 healthy subjects. After adjusting for potential other risk factors (including tobacco smoking and alcohol drinking), cannabis use was associated with a statistically significant decrease of this cancer. The risk was decreased by 48 per cent.

This association was consistent across different measures of cannabis use (current/former use, duration, and frequency of use). For participants, who used the drug for 10 to 20 years the risk was about one-third of that of non-users.

The magnitude of the reduced risk was more pronounced for those who started use after 20 years of age compared to younger age. Authors concluded that their "study suggests that moderate marijuana use is associated with reduced risk" of sqamous cell carcinoma of head and neck. They noted that experimental data have shown that cannabinoids inhibit cancer growth.

(Source: Liang C, McClean MD, Marsit C, Christensen B, Peters E, Nelson HH, Kelsey KT. A Population-Based Case-Control Study of Marijuana Use and Head and Neck Squamous Cell Carcinoma. Cancer Prev Res (Phila Pa). 2009 Jul 28. [Electronic publication ahead of print])

Also, read: Marijuana or die!
Please also read: Long Term Exposure To Cannabis

Ed Note: "For participants, who used the drug for 10 to 20 years the risk was about one-third of that of non-users."

Oh? In other words: Non-users of cannabis have about 3 times the risk of neck and head cancers when compared to users of cannabis or marijuana for 10 to 20 years.

This is the truth cleverly worded by big pharma.

As the research piles up, when can we have our medicine?

Why is it taken so long? Why is it taking so many people to die and  long for science to break through ideology?

Meanwhile, cigarettes are completely legal you can light up anywhere even when close to little children and cigarettes kill in excess of 38,000 Americans every year from passive smoke inhalation ( and believe me 38,000 is an awful lot of dead bodies from people who did not even enjoy the habit ...) Yet marijuana has killed no-one (because its toxicity is zero) and studies have shown that in a population with marijuana smokers, these are the same people who have a lower incidence of cancer than non-smokers overall, including lung cancer.