Marijuana use and risk of lung cancer: a 40-year cohort study



Cannabis (marijuana) smoke and tobacco smoke contain many of the same potent carcinogens, but a critical—yet unresolved—medical and public-health issue is whether cannabis smoking might facilitate the development of lung cancer. The current study aimed to assess the risk of lung cancer among young marijuana users.


A population-based cohort study examined men (n = 49,321) aged 18–20 years old assessed for cannabis use and other relevant variables during military conscription in Sweden in 1969–1970. Participants were tracked until 2009 for incident lung cancer outcomes in nationwide linked medical registries. Cox regression modeling assessed relationships between cannabis smoking, measured at conscription, and the hazard of subsequently receiving a lung cancer diagnosis.


At the baseline conscription assessment, 10.5 % (n = 5,156) reported lifetime use of marijuana and 1.7 % (n = 831) indicated lifetime use of more than 50 times, designated as “heavy” use. Cox regression analyses (n = 44,284) found that such “heavy” cannabis smoking was significantly associated with more than a twofold risk (hazard ratio 2.12, 95 % CI 1.08–4.14) of developing lung cancer over the 40-year follow-up period, even after statistical adjustment for baseline tobacco use, alcohol use, respiratory conditions, and socioeconomic status.


Our primary finding provides initial longitudinal evidence that cannabis use might elevate the risk of lung cancer. In light of the widespread use of marijuana, especially among adolescents and young adults, our study provides important data for informing the risk–benefit calculus of marijuana smoking in medical, public-health, and drug-policy settings.

This is a preview of subscription content, access via your institution.

Fig. 1


  1. 1.

    United Nations Office on Drugs and Crime (2010) World drug report 2010 (United Nations Publication, Sales No. E.10.XI.13). United Nations Office on Drugs and Crime, Vienna, Austria

  2. 2.

    Degenhardt L, Hall W (2012) Extent of illicit drug use and dependence, and their contribution to the global burden of disease. Lancet 379:55–70

    PubMed  Article  Google Scholar 

  3. 3.

    Mehra R, Moore BA, Crothers K (2006) The association between marijuana smoking and lung cancer: a systematic review. Arch Intern Med 166:1359–1367

    PubMed  Article  CAS  Google Scholar 

  4. 4.

    Hall W, Degenhardt L (2009) Adverse health effects of non-medical cannabis use. Lancet 374:1383–1391

    PubMed  Article  CAS  Google Scholar 

  5. 5.

    Hashibe M, Straif K, Tashkin DP, Morgenstern H, Greenland S, Zhang ZF (2005) Epidemiologic review of marijuana use and cancer risk. Alcohol 35:265–275

    PubMed  Article  CAS  Google Scholar 

  6. 6.

    Alberg AJ, Ford JG, Samet JM, American College of Chest Physicians (2007) Epidemiology of lung cancer: ACCP evidence-based clinical practice guidelines (2nd edition). Chest 132:29S–55S

    PubMed  Article  CAS  Google Scholar 

  7. 7.

    Maertens RM, White PA, Rickert W et al (2009) The genotoxicity of mainstream and sidestream marijuana and tobacco smoke condensates. Chem Res Toxicol 22:1406–1414

    PubMed  Article  CAS  Google Scholar 

  8. 8.

    Moir D, Rickert WS, Levasseur G et al (2008) A comparison of mainstream and sidestream marijuana and tobacco cigarette smoke produced under two machine smoking conditions. Chem Res Toxicol 21:494–502

    PubMed  Article  CAS  Google Scholar 

  9. 9.

    Marselos M, Karamanakos P (1999) Mutagenicity, developmental toxicity and carcinogenicity of cannabis. Addict Biol 4:5–12

    PubMed  Article  CAS  Google Scholar 

  10. 10.

    Tashkin DP, Baldwin GC, Sarafian T, Dubinett S, Roth MD (2002) Respiratory and immunologic consequences of marijuana smoking. J Clin Pharmacol 42:71S–81S

    PubMed  CAS  Google Scholar 

  11. 11.

    Barsky SH, Roth MD, Kleerup EC, Simmons M, Tashkin DP (1998) Histopathologic and molecular alterations in bronchial epithelium in habitual smokers of marijuana, cocaine, and/or tobacco. J Natl Cancer Inst 90:1198–1205

    PubMed  Article  CAS  Google Scholar 

  12. 12.

    Fligiel SEG, Roth MD, Kleerup EC, Barsky SH, Simmons MS, Tashkin DP (1997) Tracheobronchial histopathology in habitual smokers of cocaine, marijuana, and/or tobacco. Chest 112:319–326

    PubMed  Article  CAS  Google Scholar 

  13. 13.

    Tashkin DP (2001) Airway effects of marijuana, cocaine, and other inhaled illicit agents. Curr Opin Pulm Med 7:43–61

    PubMed  Article  CAS  Google Scholar 

  14. 14.

    Roth MD, Arora A, Barsky SH, Kleerup EC, Simmons M, Tashkin DP (1998) Airway inflammation in young marijuana and tobacco smokers. Am J Respir Crit Care Med 157:928–937

    PubMed  Article  CAS  Google Scholar 

  15. 15.

    Sidney S, Quesenberry CP Jr, Friedman GD, Tekawa IS (1997) Marijuana use and cancer incidence (California, United States). Cancer Cause Control 8:722–728

    Article  CAS  Google Scholar 

  16. 16.

    Aldington S, Harwood M, Cox B et al (2008) Cannabis use and risk of lung cancer: a case–control study. Eur Respir J 31:280–286

    PubMed  Article  CAS  Google Scholar 

  17. 17.

    Sasco AJ, Merrill RM, Dari I et al (2002) A case–control study of lung cancer in Casablanca, Morocco. Cancer Cause Control 13:609–616

    Article  Google Scholar 

  18. 18.

    Berthiller J, Straif K, Boniol M et al (2008) Cannabis smoking and risk of lung cancer in men: a pooled analysis of three studies in Maghreb. J Thorac Oncol 3:1398–1403

    PubMed  Article  Google Scholar 

  19. 19.

    Hashibe M, Morgenstern H, Cui Y et al (2006) Marijuana use and the risk of lung and upper aerodigestive tract cancers: results of a population-based case–control study. Cancer Epidemiol Biomarkers Prev 15:1829–1834

    PubMed  Article  CAS  Google Scholar 

  20. 20.

    Lee MH, Hancox RJ (2011) Effects of smoking cannabis on lung function. Expert Rev Respir Med 5:537–546

    PubMed  Article  CAS  Google Scholar 

  21. 21.

    Aldington S, Harwood M, Cox B et al (2008) Cannabis use and cancer of the head and neck: case–control study. Otolaryngol Head Neck 138:374–380

    Article  Google Scholar 

  22. 22.

    Otto U (1976) Males youths. A sociopsychiatric study of a total annual population of Swedish adolescent boys. Acta Psychiatr Scand Suppl 264:1–312

    PubMed  CAS  Google Scholar 

  23. 23.

    Andréasson S, Engström A, Allebeck P, Rydberg U (1987) Cannabis and schizophrenia: a longitudinal study of Swedish conscripts. Lancet 330:1483–1486

    Article  Google Scholar 

  24. 24.

    Ludvigsson JF, Otterblad-Olausson P, Pettersson BU, Ekbom A (2009) The Swedish personal identity number: possibilities and pitfalls in healthcare and medical research. Eur J Epidemiol 24:659–667

    PubMed  Article  Google Scholar 

  25. 25.

    Lunde AS, Lundeborg S, Lettenstrom GS, Thygesen L, Huebner J (1980) The person-number systems of Sweden, Norway, Denmark, and Israel. Vital Health Stat 2(84):1–59

    Google Scholar 

  26. 26.

    Zammit S, Allebeck P, Andreasson S, Lundberg I, Lewis G (2002) Self reported cannabis use as a risk factor for schizophrenia in Swedish conscripts of 1969: historical cohort study. BMJ 325:1199

    PubMed  Article  Google Scholar 

  27. 27.

    Bjartveit K, Tverdal A (2005) Health consequences of smoking 1–4 cigarettes per day. Tob Control 14:315–320

    PubMed  Article  CAS  Google Scholar 

  28. 28.

    Mattsson B, Rutqvist LE, Wallgren A (1985) Comparison between diagnoses in the Stockholm Regional Cancer Register and certified underlying causes of death. Acta Radiol Oncol 24:219–226

    PubMed  Article  CAS  Google Scholar 

  29. 29.

    Mattsson B, Rutqvist LE (1985) Some aspects on validity of breast cancer, pancreatic cancer and lung cancer registration in Swedish official statistics. Radiother Oncol 4:63–70

    PubMed  Article  CAS  Google Scholar 

  30. 30.

    Ramsey SD, Scoggins JF, Blough DK, McDermott CL, Reyes CM (2009) Sensitivity of administrative claims to identify incident cases of lung cancer: a comparison of 3 health plans. J Manag Care Pharm 15:659–668

    PubMed  Google Scholar 

  31. 31.

    Brewster D, Muir C, Crichton J (1995) Registration of lung cancer in Scotland: an assessment of data accuracy based on review of medical records. Cancer Cause Control 6:303–310

    Article  CAS  Google Scholar 

  32. 32.

    Greenland S, Lash TL (2008) Bias analysis. In: Rothman KJ, Greenland S, Lash TL (eds) Modern epidemiology, 3rd edn. Lippincott Williams & Wilkins, Philadelphia, pp 345–380

    Google Scholar 

  33. 33.

    Chao C (2007) Associations between beer, wine, and liquor consumption and lung cancer risk: a meta-analysis. Cancer Epidemiol Biomarkers Prev 16:2436–2447

    PubMed  Article  CAS  Google Scholar 

  34. 34.

    Freudenheim JL, Ritz J, Smith-Warner SA et al (2005) Alcohol consumption and risk of lung cancer: a pooled analysis of cohort studies. Am J Clin Nutr 82:657–667

    PubMed  CAS  Google Scholar 

  35. 35.

    Brenner DR, McLaughlin JR, Hung RJ (2011) Previous lung diseases and lung cancer risk: a systematic review and meta-analysis. PLoS ONE 6:e17479

    PubMed  Article  CAS  Google Scholar 

  36. 36.

    Boffetta P, Ye W, Boman G, Nyren O (2002) Lung cancer risk in a population-based cohort of patients hospitalized for asthma in Sweden. Eur Respir J 19:127–133

    PubMed  Article  CAS  Google Scholar 

  37. 37.

    Santillan AA, Camargo CA, Colditz GA (2003) A meta-analysis of asthma and risk of lung cancer (United States). Cancer Cause Control 14:327–334

    Article  Google Scholar 

  38. 38.

    Rosenberger A, Bickeböller H, McCormack V et al (2012) Asthma and lung cancer risk: a systematic investigation by the International Lung Cancer Consortium. Carcinogenesis 33:587–597

    PubMed  Article  CAS  Google Scholar 

  39. 39.

    StataCorp (2009) Stata statistical software: release 11. College Station, StataCorp LP, TX

    Google Scholar 

  40. 40.

    Hayat MJ, Howlader N, Reichman ME, Edwards BK (2007) Cancer statistics, trends, and multiple primary cancer analyses from the surveillance, epidemiology, and end results (SEER) program. Oncologist 12:20–37

    PubMed  Article  Google Scholar 

  41. 41.

    Holmberg L, Sandin F, Bray F et al (2010) National comparisons of lung cancer survival in England, Norway and Sweden 2001–2004: differences occur early in follow-up. Thorax 65:436

    PubMed  Article  Google Scholar 

  42. 42.

    Tashkin DP (2005) Smoked marijuana as a cause of lung injury. Monaldi Arch Chest Dis 63:93–100

    PubMed  CAS  Google Scholar 

  43. 43.

    Bowles DW, O’Bryant CL, Camidge DR, Jimeno A (2011) The intersection between cannabis and cancer in the United States. Crit Rev Oncol Hematol 83:1–10

    PubMed  Article  Google Scholar 

  44. 44.

    Melamede R (2005) Cannabis and tobacco smoke are not equally carcinogenic. Harm Reduct J 2:21

    PubMed  Article  Google Scholar 

  45. 45.

    Hall W, Christie M, Currow D (2005) Cannabinoids and cancer: causation, remediation, and palliation. Lancet Oncol 6:35–42

    PubMed  CAS  Google Scholar 

  46. 46.

    Pisanti S, Bifulco M (2009) Endocannabinoid system modulation in cancer biology and therapy. Pharmacol Res 60:107–116

    PubMed  Article  CAS  Google Scholar 

  47. 47.

    Pisanti S, Malfitano AM, Grimaldi C et al (2009) Use of cannabinoid receptor agonists in cancer therapy as palliative and curative agents. Best Pract Res Clin Endocrinol Metab 23:117–131

    PubMed  Article  CAS  Google Scholar 

  48. 48.

    Degenhardt L, Bucello C, Calabria B et al (2011) What data are available on the extent of illicit drug use and dependence globally? Results of four systematic reviews. Drug Alcohol Depend 117:85–101

    PubMed  Article  Google Scholar 

  49. 49.

    Hibell B, Guttormsson U, Ahlström S et al (2012) The 2011 ESPAD report: substance use among students in 36 European countries. The European School Survey Project on Alcohol and Other Drugs, Lisbon

    Google Scholar 

  50. 50.

    Wiencke JK, Kelsey KT (2002) Teen smoking, field cancerization, and a “critical period” hypothesis for lung cancer susceptibility. Environ Health Perspect 110:555–558

    PubMed  Article  Google Scholar 

  51. 51.

    Johnston LD, O’Malley PM, Bachman JG, Schulenberg JE (2011) Monitoring the future national results on adolescent drug use: overview of key findings. Institute for Social Research, The University of Michigan, Ann Arbor, MI

    Google Scholar 

  52. 52.

    Danseco ER, Kingery PM, Coggeshall MB (1999) Perceived risk of harm from marijuana use among youth in the USA. School Psychol Int 20:39–56

    Article  Google Scholar 

  53. 53.

    Swaim RC (2003) Individual and school level effects of perceived harm, perceived availability, and community size on marijuana use among 12th-grade students: a random effects model. Prev Sci 4:89–98

    PubMed  Article  Google Scholar 

  54. 54.

    Bachman JG, Johnson LD, O’Malley PM (1998) Explaining recent increases in students’ marijuana use: impacts of perceived risks and disapproval, 1976 through 1996. Am J Public Health 88:887–892

    PubMed  Article  CAS  Google Scholar 

  55. 55.

    Cuijpers P (2002) Effective ingredients of school-based drug prevention programs. A systematic review. Addict Behav 27:1009–1023

    PubMed  Article  Google Scholar 

  56. 56.

    Donaldson SI, Graham JW, Hansen WB (1994) Testing the generalizability of intervening mechanism theories: understanding the effects of adolescent drug use prevention interventions. J Behav Med 17:195–216

    PubMed  Article  CAS  Google Scholar 

  57. 57.

    White D, Pitts M (1998) Educating young people about drugs: a systematic review. Addiction 93:1475–1487

    PubMed  Article  CAS  Google Scholar 

  58. 58.

    Faggiano F, Vigna-Taglianti FD, Versino E, Zambon A, Borraccino A, Lemma P (2005) School-based prevention for illicit drugs’ use. Cochrane Database Syst Rev 18(2):003020

    Google Scholar 

  59. 59.

    Room R, Fischer B, Hall W, Lenton S, Reuter P (2010) Cannabis policy: moving beyond stalemate. Oxford University Press, New York

    Google Scholar 

  60. 60.

    Hall W, Lynskey M (2009) The challenges in developing a rational cannabis policy. Curr Opin Psychiatry 22:258–262

    PubMed  Article  Google Scholar 

  61. 61.

    Cohen PJ (2009) Medical marijuana: the conflict between scientific evidence and political ideology. Part one of two. J Pain Palliat Care Pharmacother 23:4–25

    PubMed  Article  Google Scholar 

  62. 62.

    Cohen PJ (2009) Medical marijuana: the conflict between scientific evidence and political ideology. Part two of two. J Pain Palliat Care Pharmacother 23:120–140

    PubMed  Article  Google Scholar 

  63. 63.

    Rehm J, Taylor B, Room R (2006) Global burden of disease from alcohol, illicit drugs and tobacco. Drug Alcohol Rev 25:503–513

    PubMed  Article  Google Scholar 

  64. 64.

    Chassin L, Presson CC, Rose JS, Sherman SJ (1996) The natural history of cigarette smoking from adolescence to adulthood: demographic predictors of continuity and change. Health Psychol 15:478–484

    PubMed  Article  CAS  Google Scholar 

  65. 65.

    Chen K, Kandel DB (1995) The natural history of drug use from adolescence to the mid-thirties in a general population sample. Am J Public Health 85:41–47

    PubMed  Article  CAS  Google Scholar 

  66. 66.

    Ellickson PL, Martino SC, Collins RL (2004) Marijuana use from adolescence to young adulthood: multiple developmental trajectories and their associated outcomes. Health Psychol 23:299–307

    PubMed  Article  Google Scholar 

  67. 67.

    Perkonigg A, Goodwin RD, Fiedler A et al (2008) The natural course of cannabis use, abuse and dependence during the first decades of life. Addiction 103:439–449 discussion 450–451

    PubMed  Article  Google Scholar 

  68. 68.

    Perkonigg A, Lieb R, Hofler M, Schuster P, Sonntag H, Wittchen HU (1999) Patterns of cannabis use, abuse and dependence over time: incidence, progression and stability in a sample of 1,228 adolescents. Addiction 94:1663–1678

    PubMed  Article  CAS  Google Scholar 

  69. 69.

    Benson G, Holmberg MB (1985) Validity of questionnaires in population studies on drug use. Acta Psychiatr Scand 71:9–18

    PubMed  Article  CAS  Google Scholar 

Download references


This research was supported indirectly by an institutional grant (which helped to provide salary support for Dr. Russell C. Callaghan, PhD) from the Ontario Ministry of Health and Long-Term Care to the Centre for Addiction and Mental Health (CAMH). The Ontario Ministry of Health and Long-Term Care did not have any role in the study design, analyses, interpretation of results, manuscript preparation, or approval to submit the final version of the manuscript for publication. The views expressed in this paper do not necessarily reflect those of the Ministry. This work was also funded by a research grant from the Swedish Council for Working Life and Social Research (FAS 2009-1611 to PA), which helped to provide salary support for Dr. Anna Sidorchuk, MD, PhD. The funders had no role in study design, data collection, data analyses, manuscript preparation, or approval to publish.

Conflict of interest

The authors declare that they have no conflict of interest.

Author information



Corresponding author

Correspondence to Russell C. Callaghan.

Electronic supplementary material

Below is the link to the electronic supplementary material.

Supplementary material 1 (DOCX 16 kb)

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Callaghan, R.C., Allebeck, P. & Sidorchuk, A. Marijuana use and risk of lung cancer: a 40-year cohort study. Cancer Causes Control 24, 1811–1820 (2013).

Download citation


  • Marijuana use
  • Lung cancer
  • Cohort
  • Incidence
  • Tobacco
  • Swedish conscripts