Psychedelic Use, Cannabis Co-Use, and Prostate Cancer in Older Adults | Research

The takeaway

Among men 50 and older, exclusive psychedelic use was associated with higher odds of prostate cancer, while those who used both psychedelics and cannabis had significantly lower odds than psychedelic-only users.

Cancer researchers, older adults interested in substance use effects, oncologists

4.58x higher prostate cancer odds for psychedelic-only vs co-users with cannabis

What the researchers found

Exclusive classic psychedelic use was associated with 2.62 times higher odds of prostate cancer diagnosis compared to non-users. Among adults 65 and older, the association was even stronger (AOR=3.60). Notably, psychedelic-only users had 4.58 times higher odds than those who used both psychedelics and cannabis, suggesting a potential modifying role of cannabis co-use.

Why it matters

This is the first study to examine associations between psychedelic and cannabis use patterns and prostate cancer. The finding that cannabis co-use may modify the psychedelic-cancer association is novel and generates hypotheses for further research.

The numbers in context

19,460 males (weighted: 50.8 million). 3.9% reported prostate cancer. Psychedelic-only vs non-users: AOR=2.62 (p<0.01). Ages 65+: AOR=3.60 (p<0.01). Psychedelic-only vs co-users: AOR=4.58 (p<0.01).

How the study worked

Analysis of 19,460 males aged 50+ from the 2015-2019 National Survey on Drug Use and Health. Participants were categorized as cannabis-only users, psychedelic-only users, co-users, or non-users. Multivariable logistic regression adjusted for sociodemographic, behavioral, and clinical covariates.

What this study cannot tell us

Cross-sectional design cannot establish causation. Self-reported substance use and cancer diagnosis. Lifetime use measures do not capture timing, dose, or frequency. Many potential confounders exist, including healthcare-seeking behavior.

How to read the evidence

Preliminary: cross-sectional survey data with self-reported measures, unable to establish causation or control for many potential confounders

When this study was published

Published in 2025 using 2015-2019 NSDUH data

The bigger picture

While the study cannot determine causation, the protective-appearing pattern of cannabis co-use is consistent with preclinical research suggesting cannabinoids may have anti-tumor properties. However, numerous confounders could explain these associations.

Questions still open

What biological mechanism could explain a psychedelic-prostate cancer link? Does cannabis genuinely modify cancer risk, or is this a confounding artifact? Would prospective studies confirm these associations?

Common questions

Does cannabis protect against prostate cancer?

This study cannot answer that question. It found that men who used both psychedelics and cannabis had lower prostate cancer odds than psychedelic-only users, but this is a cross-sectional association that could be explained by many factors other than a direct protective effect.

Why would psychedelic use be associated with prostate cancer?

The study identified this novel association but could not determine why it exists. Possible explanations include confounding by other factors, differences in healthcare-seeking behavior, or biological mechanisms that have not yet been studied.

Read the original research

Association between lifetime co-use of classic psychedelics and cannabis and prostate cancer diagnosis among US adults 50 years and older.

Scientific reports, 16(1), 609

View on PubMed ↗Publisher’s paper ↗

Citation

Baral, Amrit; Pan, Yue; Hlaing, WayWay M; Garcia-Romeu, Albert; Pinheiro, Paulo S; Vidot, Denise C. (2025). Association between lifetime co-use of classic psychedelics and cannabis and prostate cancer diagnosis among US adults 50 years and older.. Scientific reports, 16(1), 609. https://doi.org/10.1038/s41598-025-30172-5