Funferal

Dangers of cannabis

The Guardian has an article today about a British medical journal editorial on Cannabis. I had started writing a post accusing the authors of scaremongering because of this quote (from the Guardian coverage):

The authors, from Imperial College London and St Mary’s hospital, London, argued that 120,000 deaths are caused among 13 million tobacco smokers each year, from cancers, respiratory disorders and heart and lung disease. If the health effects were the same, the corresponding figure from 3.2 million cannabis smokers would be 30,000.

This statement is obviously meaningless and (along with similar statements) gave the impression that the authors were relying on arbitary comparisons with tobacco smoking. Then I decided to chase up the original article where I found that the case is much stronger, and the argument more subtle, than the Guardian implied:

Although the active ingredients of the cannabis plant differ from those of the tobacco plant, each produces about 4000 chemicals when smoked and these are largely identical…. We already know that regular use of cannabis is associated with an increased incidence of mental illnesses, most notably schizophrenia and depression, but it is also worth examining its potential to cause other illnesses, especially those of the heart and respiratory system…. However, despite these alarming facts, there is no evidence at present on whether smoking cannabis contributes to the progression of coronary artery disease, as smoking cigarettes does. More studies of the cardiovascular and pulmonary effects of cannabis are essential.

Of course, the editorial still has its critics, as a ‘rapid response‘ letter on the BMJ site attests. Interesting to see speculation about the relative health effects of cannabis consumed through eating, rather than smoking.