Cannabis legalization driving increases in marijuana use among U.S. adults with historically lower consumption rates

OG article by Boston College

January 21, 2026

A Boston College study published in the American Journal of Preventive Medicine analyzed recreational cannabis legalization's effects on U.S. adult use from 2016-2023, using Behavioral Risk Factor Surveillance System data from over 859,600 respondents across 38 states. Legalization drove a roughly one percentage point increase in use (about 10% relative rise from 11.9% baseline), with the most significant growth among groups historically less likely to consume: adults 60+, females, whites, and college-educated individuals (1-2 point increases, 15-37% relative). This suggests legalization broadens adoption rather than intensifying existing use. Historically, cannabis consumption has risen over decades, with 2023 showing higher rates among younger adults (25.2% past-month for 18-25), males, certain racial groups, lower education/income, or those with mental health issues. By January 2026, 24 states plus D.C. had legalized recreational use for adults 21+, mostly with commercial markets. State variations range from 7% to 22.4% use. While perceptions of risk decline, evidence grows on dependency, cognitive, cardiovascular, and respiratory harms, especially with frequent/early use. The study calls for public health education, outreach, and monitoring as policies evolve, including new measures like marijuana lounges in some states.