Long-Term Cannabis Use Leaves Marks on DNA, Dunedin Study Finds
The decades-long Dunedin birth cohort study found that long-term cannabis users had distinct DNA methylation patterns compared to non-users.
Quick Facts
What This Study Found
Analysis of the Dunedin Multidisciplinary Health and Development Study revealed that decades of cannabis use was associated with specific DNA methylation changes, a type of epigenetic modification that can alter gene expression without changing the DNA sequence itself.
Key Numbers
Drawn from the Dunedin Study, a birth cohort followed for decades; specific methylation sites and effect sizes in full text.
How They Did This
Longitudinal birth cohort study (Dunedin Study) following participants from birth, with DNA methylation profiling conducted to compare long-term cannabis users with non-users.
Why This Research Matters
Epigenetic changes represent a biological mechanism through which cannabis exposure could have lasting effects on health, potentially affecting gene regulation in ways that persist beyond active use.
The Bigger Picture
Epigenetics is an emerging frontier in understanding how environmental exposures, including drug use, leave lasting biological imprints. These findings add cannabis to the list of substances with documented epigenetic signatures.
What This Study Doesn't Tell Us
Observational design cannot confirm cannabis directly caused the methylation changes. Other lifestyle factors correlated with cannabis use could contribute. Functional significance of identified methylation changes needs further study.
Questions This Raises
- ?Do these methylation changes have clinical consequences?
- ?Are they reversible after stopping cannabis use?
- ?Could they be transmitted to offspring?
Trust & Context
- Key Stat:
- Decades-long Dunedin Study links cannabis use to DNA methylation changes
- Evidence Grade:
- One of the world's most rigorous longitudinal birth cohort studies, though observational design limits causal claims.
- Study Age:
- 2025 analysis from the ongoing Dunedin Study, which began tracking participants at birth.
- Original Title:
- DNA methylation profiles of long-term cannabis users in midlife: a comprehensive evaluation of published cannabis-associated methylation markers in a representative cohort.
- Published In:
- Molecular psychiatry, 30(10), 4576-4590 (2025)
- Authors:
- Meier, Madeline H(7), Sugden, Karen, Moffitt, Terrie E(3), Williams, Benjamin S, Bourassa, Kyle J, Houts, Renate, Ramrakha, Sandhya, Theodore, Reremoana, Caspi, Avshalom
- Database ID:
- RTHC-07111
Evidence Hierarchy
Follows a group of people over time to track how outcomes develop.
What do these levels mean? →Frequently Asked Questions
Does cannabis change your DNA?
Not the DNA sequence itself, but this study found long-term cannabis use was associated with changes in DNA methylation, an epigenetic modification that affects how genes are expressed.
What is the Dunedin Study?
A world-renowned birth cohort study from New Zealand that has followed over 1,000 people from birth through middle age, providing some of the strongest longitudinal health data available.
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Cite This Study
https://rethinkthc.com/research/RTHC-07111APA
Meier, Madeline H; Sugden, Karen; Moffitt, Terrie E; Williams, Benjamin S; Bourassa, Kyle J; Houts, Renate; Ramrakha, Sandhya; Theodore, Reremoana; Caspi, Avshalom. (2025). DNA methylation profiles of long-term cannabis users in midlife: a comprehensive evaluation of published cannabis-associated methylation markers in a representative cohort.. Molecular psychiatry, 30(10), 4576-4590. https://doi.org/10.1038/s41380-025-03042-9
MLA
Meier, Madeline H, et al. "DNA methylation profiles of long-term cannabis users in midlife: a comprehensive evaluation of published cannabis-associated methylation markers in a representative cohort.." Molecular psychiatry, 2025. https://doi.org/10.1038/s41380-025-03042-9
RethinkTHC
RethinkTHC Research Database. "DNA methylation profiles of long-term cannabis users in midl..." RTHC-07111. Retrieved from https://rethinkthc.com/research/meier-2025-dna-methylation-profiles-of
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.