Bisexual Women in Canada Had the Highest Cannabis Use Disparities

Using nationally representative Canadian data, bisexual women showed the highest disparities in cannabis use and mental health compared to heterosexual peers, while gay and bisexual men showed decreasing substance use over time.

Bellows, Zachary et al.·PloS one·2025·Strong EvidenceCross-Sectional
RTHC-06041Cross SectionalStrong Evidence2025RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
Cross-Sectional
Evidence
Strong Evidence
Sample
N=19

What This Study Found

Lesbians and bisexual women had elevated odds of cannabis use compared to heterosexual women. Bisexual women showed the highest disparities across all outcomes (mental health OR=3.3, plus elevated binge drinking, illicit drugs, and cannabis). Gay and bisexual men and lesbians showed decreasing substance use trends over time (2009-2014).

Key Numbers

Weighted N=19.98 million. Bisexual women: OR=3.3 for poor mental health. Lesbians and bisexual women had elevated cannabis use. Gay/bisexual men and lesbians showed decreasing substance use 2009-2014.

How They Did This

Analysis of 2009-2014 Canadian Community Health Surveys with a weighted sample of 19.98 million individuals. Logistic regression stratified by sex examined health disparities across sexual orientations, adjusted for covariates.

Why This Research Matters

Understanding which specific subgroups face the greatest health disparities allows for more targeted interventions. Bisexual women appear uniquely vulnerable, which aligns with research on biphobia and erasure in both heterosexual and LGBTQ+ spaces.

The Bigger Picture

While overall LGBTQ+ health disparities are well documented, disaggregating by specific sexual orientation reveals that bisexual individuals, especially women, bear a disproportionate burden. Interventions targeting "LGBTQ+" broadly may miss these specific needs.

What This Study Doesn't Tell Us

Self-reported data. 2009-2014 data may not reflect current patterns. Sexual orientation categories were broad. Those answering "don't know" or "refuse" had reduced substance use odds, suggesting measurement complexity.

Questions This Raises

  • ?Why are bisexual women uniquely affected?
  • ?Have these disparities changed since 2014?
  • ?Would biphobia-specific interventions improve outcomes?

Trust & Context

Key Stat:
Bisexual women: 3.3x higher odds of poor mental health
Evidence Grade:
Strong: nationally representative weighted sample of nearly 20 million individuals with stratified analysis, though cross-sectional and from 2009-2014
Study Age:
Published in 2025 using 2009-2014 Canadian Community Health Survey data
Original Title:
Disparities in self-reported mental health, physical health, and substance use across sexual orientations in Canada.
Published In:
PloS one, 20(3), e0305019 (2025)
Database ID:
RTHC-06041

Evidence Hierarchy

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

A snapshot of a population at one point in time.

What do these levels mean? →

Frequently Asked Questions

Which group had the highest cannabis use?

Lesbians and bisexual women had elevated cannabis use compared to heterosexual women. Bisexual women showed the highest disparities overall across mental health, physical health, and multiple substance use measures.

Are things getting better over time?

For some groups, yes. Gay and bisexual men and lesbians showed decreasing substance use trends from 2009-2014. However, bisexual women showed worsening mental health relative to heterosexual women over the same period.

Read More on RethinkTHC

Cite This Study

RTHC-06041·https://rethinkthc.com/research/RTHC-06041

APA

Bellows, Zachary; Kim, Chungah; Bai, Yihong; Cao, Peiya; Chum, Antony. (2025). Disparities in self-reported mental health, physical health, and substance use across sexual orientations in Canada.. PloS one, 20(3), e0305019. https://doi.org/10.1371/journal.pone.0305019

MLA

Bellows, Zachary, et al. "Disparities in self-reported mental health, physical health, and substance use across sexual orientations in Canada.." PloS one, 2025. https://doi.org/10.1371/journal.pone.0305019

RethinkTHC

RethinkTHC Research Database. "Disparities in self-reported mental health, physical health,..." RTHC-06041. Retrieved from https://rethinkthc.com/research/bellows-2025-disparities-in-selfreported-mental

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.