Cannabis smoking may contribute to lung disease, pneumothorax, infections, and possibly lung cancer

A review found emerging evidence that habitual cannabis smoking may contribute to COPD, pneumothorax, respiratory infections including tuberculosis, with biological plausibility for lung cancer risk.

Reid, P T et al.·The journal of the Royal College of Physicians of Edinburgh·2010·Moderate EvidenceReview
RTHC-00445ReviewModerate Evidence2010RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Review
Evidence
Moderate Evidence
Sample
Not reported

What This Study Found

The review examined evidence on respiratory effects of cannabis smoking, noting that mental health concerns had dominated cannabis research while lung effects received relatively little attention.

The authors found emerging concern that habitual cannabis smoking may contribute to chronic obstructive pulmonary disease (COPD), pneumothorax (collapsed lung), and respiratory infections including tuberculosis.

Regarding lung cancer, the review noted that biological plausibility existed for an association (cannabis smoke contains carcinogens and causes cellular changes), even though epidemiological evidence had not yet definitively established the link. The authors suggested biological evidence may precede epidemiological confirmation.

The review emphasized that cannabis research was complicated by confounding from concurrent tobacco use and other social factors.

Key Numbers

The review discussed qualitative evidence across multiple respiratory conditions but did not report pooled risk estimates.

How They Did This

Narrative review by chest physicians examining epidemiological and biological evidence for respiratory effects of cannabis smoking, published in the Journal of the Royal College of Physicians of Edinburgh.

Why This Research Matters

The review highlighted a gap between public perception of cannabis as safe and emerging evidence of respiratory harms, particularly relevant as cannabis smoking was widespread among young people.

The Bigger Picture

This review represented the perspective of chest physicians concerned that respiratory effects of cannabis were being overlooked while mental health effects dominated the research agenda.

What This Study Doesn't Tell Us

Narrative review without systematic methodology. Many referenced studies were confounded by concurrent tobacco smoking. Epidemiological evidence for lung cancer specifically was acknowledged as incomplete.

Questions This Raises

  • ?Will epidemiological studies eventually confirm the biological evidence for cannabis-related lung cancer?
  • ?How much cannabis smoking is needed to meaningfully increase respiratory disease risk?

Trust & Context

Key Stat:
Biological plausibility for lung cancer may precede epidemiological confirmation
Evidence Grade:
Narrative review by clinical experts synthesizing emerging evidence, with acknowledged limitations in the underlying research.
Study Age:
Published in 2010. Research on cannabis and respiratory health has continued with larger studies since.
Original Title:
Cannabis and the lung.
Published In:
The journal of the Royal College of Physicians of Edinburgh, 40(4), 328-3; quiz 333-4 (2010)
Database ID:
RTHC-00445

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study

Summarizes existing research on a topic.

What do these levels mean? →

Frequently Asked Questions

Can smoking cannabis cause lung disease?

The review found emerging evidence linking habitual cannabis smoking to COPD, collapsed lung, and respiratory infections. The evidence was complicated by the fact that many cannabis smokers also smoke tobacco.

Does cannabis cause lung cancer?

At the time of this review, biological evidence suggested cannabis smoke contains carcinogens, but epidemiological studies had not definitively established a lung cancer link. The authors suggested biological evidence might precede epidemiological confirmation.

Read More on RethinkTHC

Cite This Study

RTHC-00445·https://rethinkthc.com/research/RTHC-00445

APA

Reid, P T; Macleod, J; Robertson, J R. (2010). Cannabis and the lung.. The journal of the Royal College of Physicians of Edinburgh, 40(4), 328-3; quiz 333-4. https://doi.org/10.4997/JRCPE.2010.417

MLA

Reid, P T, et al. "Cannabis and the lung.." The journal of the Royal College of Physicians of Edinburgh, 2010. https://doi.org/10.4997/JRCPE.2010.417

RethinkTHC

RethinkTHC Research Database. "Cannabis and the lung." RTHC-00445. Retrieved from https://rethinkthc.com/research/reid-2010-cannabis-and-the-lung

Access the Original Study

Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.

This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.