What Does Weed Do To Your Lungs?

The effect that smoking weed has on your lungs has long been a source of controversy.  Despite the assumption that smoking marijuana may have similar long-term effects as smoking tobacco, researchers have not been able to establish such a relationship.

That is particularly interesting since marijuana smoke does contain several carcinogens, or cancer-causing chemicals.  Smoking weed increases the presence of tar in the lungs and can lead to inflammation in your airways.  However, scientific studies to date have not found a significant correlation between light to moderate marijuana smoking and lung cancer.  In fact, marijuana smokers do not even seem to show evidence of decreased lung health.  A 2015 study found that long-term marijuana smokers consuming up to one joint per day did not have a diminished expiratory volume, a common measure of lung health, compared to non-smokers.

A number of studies have looked at whether or not smoking weed is linked to other respiratory conditions, such as pneumothorax (collapsed lung) or chronic obstructive pulmonary disease (COPD).  However, no studies have been able to conclusively link smoking marijuana to serious lung or upper respiratory conditions.

The best evidence suggests that light to moderate weed smokers may experience some respiratory side effects such as coughing, wheezing, or sore throat.  However these effects diminish once a person stops smoking and do not seem to have a long-term impact on lung and airway health.  It remains unclear what long-term effects heavy marijuana smokers experience in terms of cancer risk and overall lung health.  Interestingly, THC and CBD are both antioxidants and may offer some protective measures against respiratory damage from smoking weed.  That may partially explain why scientists have not found a strong relationship between weed smoking and lung cancer to date.

Marijuana can also be consumed in different ways that diminish or eliminate the impacts on respiratory and lung health.  The consumption of edibles has no impact on the lungs at all, and people who use vaporizers experience fewer respiratory effects than users that prefer joints or pipes.  Indeed, one of the factors that may affect respiratory health is the consumption of rolling paper.  Chemicals in the paper can aggravate the tissue in your respiratory tract, causing more inflammation than using a vaporizer.  Because marijuana smoke contains many chemicals that could potentially negatively impact lung health, some leading scientists, such as Dr. Donald Tashkin of the David Geffen School of Medicine at UCLA, have advocated that marijuana would preferably be consumed via other methods until we have more scientific evidence about the effects of marijuana smoke on human health.