Cannabis Legalization Drives New Users Rather Than Heavier Use Among Existing Users

Recreational cannabis legalization increased the likelihood of any cannabis use by about 10% but did not increase frequency among existing users, with the greatest uptake among groups that historically used less: older adults, women, White adults, and college graduates.

Hawkins, Summer Sherburne et al.·American journal of preventive medicine·2026·Strong Evidencequasi-experimental
RTHC-08327Quasi ExperimentalStrong Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
quasi-experimental
Evidence
Strong Evidence
Sample
N=859,600

What This Study Found

Legalization was associated with 44% lower odds of zero cannabis use (95% CI=40-48%), indicating more people trying cannabis, but not with greater frequency among existing users — and groups with historically lower use (age 60+, female, White, college-educated) showed the strongest response with 1-2 percentage point increases.

Key Numbers

N=859,600; 38 states; 44% lower odds of zero use; 0.94 percentage point increase in use prevalence (9.8% relative increase); greatest increases among age 60+, female, White, college-educated (1-2 pp increases; all interaction p<0.1)

How They Did This

Quasi-experimental difference-in-differences analysis of 2016-2023 BRFSS data from 859,600 adults in 38 states, using zero-inflated negative binomial and probit regressions with demographic/policy controls and state/year fixed effects.

Why This Research Matters

This clarifies a key policy debate: legalization is expanding who uses cannabis rather than intensifying use among those who already do — information critical for designing proportionate public health responses.

The Bigger Picture

Legalization's primary effect is democratizing cannabis use across demographics rather than creating heavier users — a finding that should reassure some concerns while highlighting the need for education among new user populations.

What This Study Doesn't Tell Us

BRFSS self-report may underestimate use; 30-day use window may miss patterns; difference-in-differences assumes parallel trends; implementation heterogeneity across states; cannot separate legalization from commercialization effects.

Questions This Raises

  • ?Will these new users eventually increase frequency?
  • ?Do new older/female users face different health risks?
  • ?Would pre-legalization education prevent uptake among groups responding most to legalization?

Trust & Context

Key Stat:
Evidence Grade:
Very large quasi-experimental study with robust methodology and comprehensive subgroup analyses, providing strong evidence for differential legalization effects.
Study Age:
Published 2026; covers 2016-2023 across 38 US states.
Original Title:
The Impact of Recreational Cannabis Legalization on Cannabis Use in U.S. Adults From 2016 to 2023: A Quasi-Experimental Study.
Published In:
American journal of preventive medicine, 108221 (2026)
Database ID:
RTHC-08327

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

Does legalization make people use more cannabis?

It makes more people use cannabis (about 10% increase in prevalence), but those who already used didn't increase their frequency — legalization primarily brings new users in rather than intensifying existing use.

Who starts using cannabis after legalization?

Older adults (60+), women, White adults, and college graduates — groups that historically used cannabis at lower rates — showed the biggest increases in use after legalization.

Read More on RethinkTHC

Cite This Study

RTHC-08327·https://rethinkthc.com/research/RTHC-08327

APA

Hawkins, Summer Sherburne; Baidoo, Christopher E; Coley, Rebekah Levine; Centanni, Ryan S; Baum, Christopher F. (2026). The Impact of Recreational Cannabis Legalization on Cannabis Use in U.S. Adults From 2016 to 2023: A Quasi-Experimental Study.. American journal of preventive medicine, 108221. https://doi.org/10.1016/j.amepre.2025.108221

MLA

Hawkins, Summer Sherburne, et al. "The Impact of Recreational Cannabis Legalization on Cannabis Use in U.S. Adults From 2016 to 2023: A Quasi-Experimental Study.." American journal of preventive medicine, 2026. https://doi.org/10.1016/j.amepre.2025.108221

RethinkTHC

RethinkTHC Research Database. "The Impact of Recreational Cannabis Legalization on Cannabis..." RTHC-08327. Retrieved from https://rethinkthc.com/research/hawkins-2026-the-impact-of-recreational

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.