Living Near More Dispensaries Increases Young Adult Cannabis Use

Each additional cannabis dispensary within one mile of home was associated with a 5-6% increased risk of cannabis use among young adults in California, with similar findings whether using government or web-scraped dispensary data.

Harlow, Alyssa F et al.·Addiction (Abingdon·2026·Moderate Evidencelongitudinal
RTHC-08323LongitudinalModerate Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
longitudinal
Evidence
Moderate Evidence
Sample
N=2,277

What This Study Found

Each additional dispensary within 1 mile of home increased past 6-month cannabis use risk by 5-6% (registry data) or 3-4% (web-scraped data), with positive associations for smoked and edible use frequency, but not consistently for vaping frequency or daily use.

Key Numbers

N=2,277; 3 waves (2021-2023); 5-6% increased risk per dispensary (registry); 3-4% (web-scraped); smoked IRR=1.08 (registry), 1.04 (web-scraped); edible IRR=1.07/1.04; not significant for daily/near-daily use

How They Did This

Prospective cohort of 2,277 young adults (mean age 22) from California with three waves of data (2021-2023), comparing generalized linear models using government-maintained licensed dispensary registry vs. web-scraped list including unlicensed dispensaries.

Why This Research Matters

As cities and states decide where to allow dispensaries, this study provides evidence that dispensary density directly increases cannabis use among nearby young adults — relevant for zoning and licensing decisions.

The Bigger Picture

Dispensary proximity matters for cannabis use patterns, but the effect is on initiation and frequency rather than escalation to daily use — suggesting access increases casual use more than problematic use.

What This Study Doesn't Tell Us

California-specific sample; observational despite longitudinal design; 1-mile radius may not capture all access patterns; web-scraped data captures unlicensed shops but may be incomplete; confounders related to neighborhood self-selection.

Questions This Raises

  • ?Would limiting dispensary density reduce youth cannabis use?
  • ?Do the effects differ for medical vs. recreational dispensaries?
  • ?Is there a saturation point beyond which additional dispensaries have no incremental effect?

Trust & Context

Key Stat:
Evidence Grade:
Prospective cohort with repeated measures and dual data source comparison strengthens findings, though observational design limits causal conclusions.
Study Age:
Published 2026; covers 2021-2023 California data.
Original Title:
Cannabis dispensary exposure and smoked, vaped and edible cannabis use among young adults: Comparison of web-scraped and government-maintained registries.
Published In:
Addiction (Abingdon, England) (2026)
Database ID:
RTHC-08323

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

Do more dispensaries mean more cannabis use?

Yes — this California study found that each additional dispensary within 1 mile of a young adult's home increased their risk of cannabis use by 5-6%, particularly for smoking and edible consumption.

Does living near dispensaries lead to daily cannabis use?

Not necessarily — while dispensary proximity increased the likelihood of any cannabis use and use frequency, it was not consistently associated with daily or near-daily use.

Read More on RethinkTHC

Cite This Study

RTHC-08323·https://rethinkthc.com/research/RTHC-08323

APA

Harlow, Alyssa F; Williams, Michael P; Pacula, Rosalie Liccardo; Leventhal, Adam M; Pedersen, Eric R; Cockburn, Myles G; Thompson, Laura K; Cho, Junhan; Barrington-Trimis, Jessica L; Haley, Danielle F. (2026). Cannabis dispensary exposure and smoked, vaped and edible cannabis use among young adults: Comparison of web-scraped and government-maintained registries.. Addiction (Abingdon, England). https://doi.org/10.1111/add.70356

MLA

Harlow, Alyssa F, et al. "Cannabis dispensary exposure and smoked, vaped and edible cannabis use among young adults: Comparison of web-scraped and government-maintained registries.." Addiction (Abingdon, 2026. https://doi.org/10.1111/add.70356

RethinkTHC

RethinkTHC Research Database. "Cannabis dispensary exposure and smoked, vaped and edible ca..." RTHC-08323. Retrieved from https://rethinkthc.com/research/harlow-2026-cannabis-dispensary-exposure-and

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.