Cannabis smoking poses fewer pulmonary risks than tobacco smoking and is not positively associated with the development of emphysema, according to medical imaging data published in the journal Current Problems in Diagnostic Radiology. Harvard Medical School researchers compared chest CT scans of 285 subjects. Eighty-nine participants were non-smokers, 97 smoked tobacco and 99 smoked cannabis.
Participants who smoked tobacco exhibited greater damage to their hearts and lungs than did those who exclusively smoked cannabis. Specifically, tobacco smokers were far more likely to demonstrate moderate to severe coronary artery calcifications and suffer from emphysema. “The findings of our study collectively highlight the distinct patterns of pulmonary and cardiovascular manifestations associated with smoking and ‘marijuana’ use” the study’s authors concluded. “It appears that, in general, ‘marijuana’ users do not appear to develop emphysema or pulmonary hyperinflation”.
Their conclusion is consistent with several other studies finding that cannabis smoke and tobacco smoke are not equally carcinogenic and that cannabis smoke exposure is not linked to higher risks of either COPD, emphysema, lung cancer, or other tobacco-related harms. Moreover, the use of vaporisation technology, which heats herbal cannabis to a set temperature below the point of combustion, is associated with reduced exposure to toxic gasses and has been identified as a “safe and effective” cannabis delivery device in clinical trial settings.
7 May, 2025