Puff or pass? The truth about vaping, marijuana, and tobacco safety

Background: Cannabis and electronic cigarettes (EC) are often perceived as safer than combustible tobacco, yet contemporary evidence shows important pulmonary risks. Cannabis use has shifted toward high-potency products and aerosolized delivery (vaping, dabbing). Methods: We performed a targeted narrative review of PubMed/MEDLINE, Web of Science, Scopus, and the Cochrane Library, supplemented by manual reference review, emphasizing English-language studies relevant to pulmonary outcomes of cannabis, electronic cigarettes, and tobacco. Results: Although acute bronchodilation is described, chronic use is linked to respiratory symptoms and airway injury, and rare complications (e.g., bullous disease). In large cohorts of older smokers, moderate marijuana use was not clearly associated with accelerated chronic obstructive pulmonary disease (COPD) progression; however, heavy lifetime exposure may increase chronic bronchitis symptoms. EC aerosols contain nicotine and/or Δ 9 -tetrahydrocannabinol, solvents, metals, and flavorants; menthol increases inhaled particle counts and associates with worse spirometry. The 2019 EC or vaping-associated lung injury (EVALI) outbreak, strongly linked to vitamin E acetate contamination and underscores the hazards of illicit and/or poorly regulated products. In two studies of long smoking histories, EC use correlated with chronic bronchitis and did not improve cessation; however, more recent evidence from multiple randomized controlled trials and meta-analyses indicates that ECs that contain nicotine are more effective than nicotine replacement therapy or behavioral support alone for smoking cessation, although long-term safety and relapse outcomes remain uncertain. Regular cannabis smoking is associated with chronic bronchitis symptoms, airway inflammation, and impaired mucociliary function, although its long-term impact on COPD or lung cancer risk remains less clearly established than that of tobacco. Conclusion: Neither cannabis nor ECs are harmless: risk depends on the product, dose, delivery, and context. Clear regulation, accurate labeling, and longitudinal studies, especially those disentangling tobacco confounding, are needed to inform clinical guidance and policy.