Cannabis users have airway health which is closer to that of non-smokers than tobacco users, according to new research from the University of California Davis Lung Center.
Researchers collected breath samples from 285 participants to analyse the toxic profiles of those who smoke or vape cannabis, those who smoke tobacco or vape nicotine products, and those who abstain entirely. The results, published in the journal Respiratory Research, revealed striking differences between cannabis and tobacco users.
Tobacco smokers and nicotine e-vape users all displayed similar toxic breath profiles with elevated levels of inflammatory oxylipins. In contrast, cannabis smokers and vapers showed breath profiles remarkably similar to non-users, with some cannabis consumers even exhibiting lower toxicant levels than those who abstained completely.
“Cigarettes upregulate these inflammatory fatty acids, but we didn’t see that nearly as much with marijuana and marijuana products,” noted one of the study’s authors. “When we look at the signatures from the marijuana smokers, they look closer to non-users and non-smokers than the tobacco smokers, and that was a surprise to us.”
The study participants included 285 participants, comprising 89 non-smokers, 97 smokers, and 99 cannabis users.
To collect samples, participants breathed into a container for 20 minutes. The samples were filtered to remove saliva and frozen at minus 80°C before analysis. Researchers specifically examined levels of inflammatory oxylipins, typically elevated in tobacco smokers, and 403 ‘significant metabolites’ associated with tobacco smoke.
“Targeted measurements of oxylipin inflammatory markers found significant up-regulation among those using tobacco products relative to non-users. Cannabis users exhibited oxylipin levels closer to and often downregulated compared to nonusers,” the researchers reported in the journal Respiratory Research.
The findings come as cannabis use continues to rise globally, particularly in the US, where nearly half of the states have legalised recreational use. The results align with previous research that has determined cannabis consumers are exposed to fewer harmful toxicants compared to tobacco smokers. Other studies have concluded that cannabis smoke and tobacco smoke are not equally carcinogenic.
However, the researchers emphasised that their study focused solely on evaluating toxicity levels in breath samples and was not designed to establish links between these markers and specific illnesses such as lung diseases.
“While the approach allows for the identification of key inflammatory biomarkers (oxylipins), it does not seek to establish direct links to clinical outcomes, such as lung disease or respiratory dysfunction, limiting conclusions about the clinical impact of these biomarkers,” the study authors concluded.
