Smoking cannabis damages your lungs

FHX kindly sent me this link to a Guardian article claiming that smoking a joint is much more dangerous to your lungs than smoking cigarettes. Note that this is different from the claim that smoking cannabis causes lung cancer – that is not being asserted here.

The article states:

A single cannabis joint may cause as much damage to the lungs as five chain-smoked cigarettes, research has found. Medical examinations of cannabis and cigarette smokers found the drug increased specific lung problems, including obstructed airways and hyperinflation, a condition where too much air remains in the lungs when a person exhales.

Smoking one cannabis joint caused damage equivalent to smoking 2.5 to five cigarettes in rapid succession, researchers at the Medical Research Institute of New Zealand found. Doctors who carried out the study believe the damage is linked to the difference in the way cannabis is usually smoked, with users inhaling hard, holding their breath for longer and failing to use filters.

The report follows a flurry of confessions from ministers who admitted having used the illegal drug and comes days after a review of cannabis research, published in the Lancet medical journal, revealed that cannabis use may be to blame for 800 cases of serious psychosis in Britain.

The scientists set out to investigate whether smoking cannabis put users at greater risk of developing emphysema, a progressive and potentially fatal lung disease.

A group of 339 volunteers aged 18 to 70 were divided into four groups according to whether they smoked only cannabis, only tobacco, both, or were non-smokers. Each volunteer was then subjected to lung function tests and x-ray scans of their chests to assess the level of damage to their lungs and airways.

In the study, published in the journal Thorax, all smokers complained of coughs and wheezing, while only tobacco smokers showed signs of emphysema. Coughing was reduced among people who smoked cannabis and tobacco, possibly because these people smoked pure cannabis joints and so less tobacco leaf.

The extent of lung damage was directly related to the number of joints smoked. "The most important finding was that one joint of cannabis was similar to 2.5 to five tobacco cigarettes in terms of causing airflow obstruction," the authors write. "This pattern is likely to relate to the different characteristics of the cannabis joint and the way in which it is smoked. Cannabis is usually smoked without a filter and to a shorter butt length, and the smoke is a higher temperature," they add.

I made a similar claim o these in an earlier post – indeed the link to that earlier article has vaporised but I believe from memory it was referring to the same NZ study.

In relation to lung cancer issues there are contrary results and even some preliminary findings that cannabis may have a protective effect. The finding is one that I now, given the months I have spent reading about smoking is one I have no doubts about. I can’t imagine anything more damaging to your lungs than holding hot smoke in it for as long a period as possible to maximise the effect of getting stoned.

If you must smoke cannabis (something I do not recommend) eat it in cookies - don’t smoke it.