When it comes to cannabis and our health, there’s a lot we don’t know. What we do “know” is often just plausible misinformation. That’s the situation with cannabis and lungs health, too: googling the topic will yield articles that claim that smoking cannabis has no ill effect at all, as well as a 2012 report by the British Lung Foundation that claims cannabis is 20x more carcinogenic than tobacco. They’re both on the first page! Clearly these can’t both be true, so let’s get to the bottom of it.
Does Cannabis Cause Lung Cancer?
Probably not. Burned plant matter of all kinds contains chemicals and particles that are harmful to lung health, and (contrary to what some people say) cannabis smoke does contain some of the carcinogens that tobacco smoke does. In fact, cannabis contains more of some of them. However, the effect that these compounds have on the lung is more complicated than just the amount. Some of the complicating factors are:
- Different inhalation habits. Cigarette smokers frequently take smaller hits, while cannabis smokers inhale deeply and hold the smoke in their lungs. This increases the amount of tar that is left in the lungs.
- Different amounts of smoke inhaled. If one joint has three times the amount of carcinogens as a cigarette, but you smoke one joint per day instead of eight cigarettes, the fact that cannabis contains more carcinogens is outweighed by the fact that the cigarette smoker takes in significantly more carcinogens overall.
- Combination effects. Much like cannabinoids and terpenes modify the effects of THC via the entourage effect, the other compounds found in burning plant matter can affect the function of the present carcinogens. Nicotine appears to “enhance” the cancer-causing effects, while THC seems to protect against them.
The idea that cannabis doesn’t contain any carcinogens is a myth. However, fortunately for us, THC seems to protect against them. Long-term studies on heavy smokers have not been conducted yet; it’s possible that over a long enough period of time and with enough cannabis consumed, smoking cannabis could contribute to cancer. Based on what we know currently, it seems unlikely.
Does Smoking Cannabis Harm My Lungs?
Unfortunately, it probably does. Cannabis smoke is only 12% cannabinoid content – the rest is non-beneficial particulate and other compounds. Smoke irritates the airways, causing inflammation. Which long-term smoking, this can lead to symptoms like coughing, wheezing, shortness of breath, excess mucus production, tight chest, and even the development of chronic bronchitis. Of course, this depends on how much cannabis you consume, and by what methods.
Strangely, some studies have shown that by some methods of measurement, light or moderate cannabis use can actually improve lung function. A study performed by the American Thoracic Society showed amongst their participants, inhaling one joint per day for 20 years did not cause any adverse effects on lung health. Another study showed that cannabis use did not reduce the lung’s volume or lead to any disease of the small airways. However, this study also showed that using cannabis increased symptoms of coughing and shortness of breath. So, cannabis isn’t completely safe, but it won’t be taking a wrecking ball to your lungs the way tobacco does. As with all things, the key is moderation… and just to be safe, you may want to consider switching over to vaping.