Marijuana and Cancer


Less than a month ago, the NYT ran an op-ed backing the FDA's recent political decision to dismiss the health benefits of marijuana. The basic argument was that smoking marijuana can harm you for the same reason smoking tobacco can harm you. Money quote:

In their 1999 report, the Institute of Medicine's panel of experts flatly rejected the idea that herbal (usually smoked) cannabis would ever be considered a safe and effective medicine for widespread use. They noted that ... because smoked marijuana can increase the risk of lung damage, cancer and complications during pregnancy, it is appropriate only for short-term use (less than six months) by acutely suffering patients who have failed to find relief with other therapies and who are under the close supervision of a doctor.

Today we actually have some new data on the relationship between pot-smoking and lung cancer. There isn't any:

Marijuana smoking does not increase a person's risk of developing lung cancer, according to the findings of a new study at the University of California Los Angeles that surprised even the researchers. They had expected to find that a history of heavy marijuana use, like cigarette smoking, would increase the risk of cancer.

Instead, the study, which compared the lifestyles of 611 Los Angeles County lung cancer patients and 601 patients with head and neck cancers with those of 1,040 people without cancer, found no elevated cancer risk for even the heaviest pot smokers. It did find a 20-fold increased risk of lung cancer in people who smoked two or more packs of cigarettes a day.


[Dr. Donald Tashkin, senior researcher and professor at the UCLA School of Medicine] theorized that tetrahydrocannabinol, or THC, a chemical in marijuana smoke that produces its psychotropic effect, may encourage aging, damaged cells to die off before they become cancerous.

You mean smoking pot might even prevent lung cancer? I wish anti-medical marijuana advocates would be honest and simply say: we oppose this medicine because it might give people pleasure as well as helping them. Then we'd at least be able to have an honest debate.