{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T11:44:25Z","timestamp":1792064665464,"version":"4.4.0"},"reference-count":30,"publisher":"Maad Rayan Publishing Company","content-domain":{"domain":["ahj.kmu.ac.ir"],"crossmark-restriction":false},"short-container-title":["Addict Health"],"published-print":{"date-parts":[[2026,7,4]]},"abstract":"<jats:p>Introduction: Marijuana (cannabis) use has become increasingly prevalent worldwide, raising concerns about its potential long-term health effects, particularly on the respiratory system. While tobacco smoking is a well-established risk factor for lung cancer,the association between cannabis use and lung cancer risk remains unclear and controversial. This systematic review and meta-analysis of existing observational studies aimed to evaluate the potential relationship between marijuana use and the risk ofdeveloping lung cancer.Methods: A systematic search was conducted across PubMed, Web of Science, and Scopus to identify cohort and case-controlstudies up to September 2025. Studies were selected, relevant data were extracted, and statistically analyzed using effect sizes (ES)and 95% confidence intervals (CI). All analyses were conducted using STATA software.Findings: This meta-analysis included six observational studies, comprising 16 effect sizes, consisting of two cohort studies andfour case-control studies. The pooled analysis of the cohort studies (7 effect sizes) indicated a statistically significant associationbetween marijuana (cannabis) smoking and increased lung cancer risk (ES: 2.06; 95% CI: [1.04\u20134.07]; P=0.038; I\u00b2=75%). Incontrast, the meta-analysis of the case-control studies (9 effect sizes) showed a non-significant increase in risk (ES: 1.16; 95% CI:[0.71\u20131.88]; P=0.542; I\u00b2=82%).Conclusion: This meta-analysis indicates that marijuana smoking may increase lung cancer risk, with cohort studies showing asignificant twofold association. Although case-control studies were not statistically significant, the upward trend highlights theimportance of considering cannabis use in lung cancer risk assessments and patient counseling.<\/jats:p>","DOI":"10.34172\/ahj.1710","type":"journal-article","created":{"date-parts":[[2026,10,15]],"date-time":"2026-10-15T10:45:32Z","timestamp":1792061132000},"page":"1710","update-policy":"https:\/\/doi.org\/10.34172\/crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Marijuana (Cannabis) Smoking Increases the Risk of Lung Cancer: Evidence from a Systematic Review and Meta-Analysis"],"prefix":"10.34172","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-4388-0214","authenticated-orcid":true,"given":"Mehdi","family":"Karimi","sequence":"first","affiliation":[{"name":"Faculty of Medicine, Bogomolets National Medical University (NMU), Kyiv, Ukraine"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-0777-7646","authenticated-orcid":true,"given":"Kimia","family":"Kazemi","sequence":"additional","affiliation":[{"name":"Department of Food Science and Technology, Ayatollah Amoli Branch, Islamic Azad University, Amol, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6752-2765","authenticated-orcid":true,"given":"Mohammad Hossein","family":"Pourhanifeh","sequence":"additional","affiliation":[{"name":"Research Center for Biochemistry and Nutrition in Metabolic Diseases, Institute for Basic Sciences, Kashan University of Medical Sciences, Kashan, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8572-9727","authenticated-orcid":true,"given":"Parsa","family":"Irajian","sequence":"additional","affiliation":[{"name":"Physiology Research Center, Iran University of Medical Sciences, Tehran, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7740-4711","authenticated-orcid":true,"given":"Omid","family":"Asbaghi","sequence":"additional","affiliation":[{"name":"Cancer Research Center, Shahid Beheshti University of Medical Sciences (SBUMS), Tehran, Iran"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"20123","published-online":{"date-parts":[[2026,7,4]]},"reference":[{"key":"R1","first-page":"68","article-title":"Global impacts of legalization and decriminalization of marijuana and cannabis","volume":"4","author":"Mollner KL","year":"2022","journal-title":"University of Lynchburg DMSc Doctoral Project Assignment Repository"},{"key":"R2","doi-asserted-by":"publisher","DOI":"10.46234\/ccdcw2024.116"},{"key":"R3","doi-asserted-by":"publisher","DOI":"10.1055\/s-0044-1785679"},{"key":"R4","doi-asserted-by":"publisher","DOI":"10.1016\/j.eclinm.2024.103033"},{"key":"R5","doi-asserted-by":"crossref","unstructured":"Benhamou S, Hill C, Koscielny S. 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