Weekly cannabis use in childhood accelerated biological aging by up to 3.8 years into adulthood
Weekly cannabis use and depressive symptoms in childhood were each independently associated with accelerated DNA methylation aging from adolescence to adulthood, with combined effects equivalent to 3-4 extra years of biological aging.
Quick Facts
What This Study Found
Weekly cannabis use was significantly associated with accelerated DNA methylation aging (b=1.665, p=.005), as were years of weekly use (b=0.718, p=.012) and depressive symptoms (b=0.314, p=.014). In combined models, the cumulative effect of mental health symptoms, substance use, and adversity was equivalent to 3.17-3.76 additional years of biological aging.
Key Numbers
381 participants tracked from adolescence to adulthood. 1,950 total childhood assessments. Weekly cannabis use: b=1.665 (p=.005). Years of weekly use: b=0.718 (p=.012). Depression: b=0.314 (p=.014). Combined effect: 3.17-3.76 years of accelerated aging.
How They Did This
Longitudinal study of 381 participants from the Great Smoky Mountains Study. DNA methylation was measured from blood in adolescence (mean age 13.9) and adulthood (mean age 25.9). Childhood mental health, substance use, and adversity were assessed through 1,950 structured diagnostic interviews with participants and parents.
Why This Research Matters
Accelerated biological aging is linked to earlier onset of age-related diseases. Finding that cannabis use and depression independently speed up this process suggests early intervention on both fronts could have long-term health benefits.
The Bigger Picture
This study bridges the gap between childhood experiences and adult biological outcomes. The finding that cannabis and depression independently accelerate aging through the same biological mechanism (DNA methylation) suggests a shared risk pathway that compounds over time.
What This Study Doesn't Tell Us
Blood-based DNA methylation may not reflect brain-specific changes. Observational design cannot prove causation. Sample is from a single US community (Appalachian). Methylation aging clocks are estimates, not direct measures of biological age.
Questions This Raises
- ?Is the accelerated aging reversible if cannabis use and depression are treated?
- ?Do different cannabis use patterns (frequency, potency, age of onset) have different effects on methylation aging?
- ?Would similar findings emerge in a more diverse population?
Trust & Context
- Key Stat:
- 3-4 extra years of biological aging from combined risk factors
- Evidence Grade:
- Well-designed longitudinal study with objective biological measure and extensive childhood assessments. Limited by single-community sample and observational design.
- Study Age:
- Published in 2024 in the Journal of the American Academy of Child and Adolescent Psychiatry.
- Original Title:
- The Impact of Childhood Mental Health and Substance Use on Methylation Aging Into Adulthood.
- Published In:
- Journal of the American Academy of Child and Adolescent Psychiatry, 63(8), 825-834 (2024)
- Authors:
- Clark, Shaunna L(3), McGinnis, Ellen W, Zhao, Min(3), Xie, Linying, Marks, Garrett T, Aberg, Karolina A, van den Oord, Edwin J C G, Copeland, William E
- Database ID:
- RTHC-05215
Evidence Hierarchy
Frequently Asked Questions
Does cannabis age you faster?
This study found weekly cannabis use during childhood was associated with accelerated DNA methylation aging into adulthood. Combined with depression and adversity, the effect was equivalent to 3-4 extra years of biological aging by the mid-20s.
What is DNA methylation aging?
DNA methylation is a chemical modification to DNA that changes predictably with age. Researchers can estimate biological age from these patterns. When biological age exceeds chronological age, it is called accelerated aging and is linked to higher disease risk.
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Cite This Study
https://rethinkthc.com/research/RTHC-05215APA
Clark, Shaunna L; McGinnis, Ellen W; Zhao, Min; Xie, Linying; Marks, Garrett T; Aberg, Karolina A; van den Oord, Edwin J C G; Copeland, William E. (2024). The Impact of Childhood Mental Health and Substance Use on Methylation Aging Into Adulthood.. Journal of the American Academy of Child and Adolescent Psychiatry, 63(8), 825-834. https://doi.org/10.1016/j.jaac.2023.10.014
MLA
Clark, Shaunna L, et al. "The Impact of Childhood Mental Health and Substance Use on Methylation Aging Into Adulthood.." Journal of the American Academy of Child and Adolescent Psychiatry, 2024. https://doi.org/10.1016/j.jaac.2023.10.014
RethinkTHC
RethinkTHC Research Database. "The Impact of Childhood Mental Health and Substance Use on M..." RTHC-05215. Retrieved from https://rethinkthc.com/research/clark-2024-the-impact-of-childhood
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.