Longitudinal Study: Cannabis’ Impact on Lung Health Distinct from Tobacco

Dunedin, New Zealand: Smoking cannabis long-term is not associated with the same physiological consequences on lung health as is tobacco smoking, according to longitudinal data published in the American Journal of Respiratory and Critical Care Medicine.

A team of New Zealand researchers examined the long-term effects of cannabis smoking and/or tobacco smoking in a cohort of 881 middle-aged adults. 

Consistent with prior studies, researchers reported that cannabis inhalation was associated with higher total lung capacity and other physiological changes that are distinct from the health consequences associated with tobacco smoking. Authors concluded, “[I]t is increasingly clear that cannabis has different effects on lung function [as compared] to tobacco and the effects of widespread cannabis use will not necessarily mirror the harms caused by tobacco smoking.”

The findings are consistent with prior research concluding that cannabis smoke and tobacco smoke are not equally carcinogenic, that cannabis inhalation exposes consumers to fewer toxicants than does tobacco smoking, and that marijuana smoke exposure is typically not associated with the same health consequences as is tobacco smoking, including increased risks of COPD or lung cancer. Moreover, the use of vaporization 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 trials.

Full text of the study, “Differential effects of cannabis and tobacco on lung function in mid-adult life,” appears in theAmerican Journal of Respiratory and Critical Care Medicine. Additional information is available in the NORML fact sheet, ‘Cannabis Exposure and Lung Health.”