2025 Theses Doctoral

The Relationship between Marijuana Legalization and Health Behaviors Among a National Sample of Young Adults Ages 18 - 25 Years in the United States

Kim, Yewn Jung

Marijuana is the third most commonly consumed controlled substance globally and the most widely used illicit drug under federal law in the United States. Its use among young adults aged 18–25 increased significantly in 2021, reaching historic highs since 1988. This study examines the complex relationship between marijuana legalization and its social, behavioral, and health-related consequences for young adults in the U.S. By analyzing variations in marijuana use across demographic groups, belief systems, and behavioral patterns in states with differing legalization policies, the research assesses the broader policy implications.

Utilizing data from the National Survey on Drug Use and Health (NSDUH), this study employs multiple quantitative methods, including crosstabulations, correlation analyses, Chi-square tests, independent sample t-tests, and binary logistic regression, to investigate these associations, which is a step toward answering each research question.

The findings indicate that legalization does not uniformly improve public health outcomes and often results in mixed effects, particularly for marginalized populations. Young adults from lower-income backgrounds report higher marijuana use in legalized states, suggesting that financial stress and targeted marketing may influence consumption. Additionally, marijuana use was notably high in some non-legalized states, challenging the assumption that prohibition successfully prevents use. Racial disparities in marijuana use and enforcement persist, and cultural and religious beliefs significantly shape attitudes toward legalization. Furthermore, the study confirms strong correlations between marijuana use and mental health issues, substance abuse, and risky behaviors such as impaired driving. These insights underscore the need for targeted public health strategies, stricter regulatory oversight, and increased access to mental health and substance use services.

In conclusion, while legalization was intended for a healthier society, it has introduced unexpected challenges, particularly for underprivileged communities. Policymakers are encouraged to refine existing policies with a concentration on health equity, ensuring regulations alleviate risks and address structural disparities. Future research should continue monitoring long-term trends and exploring the multifaceted implications of marijuana legalization across diverse populations. By refining policies and prioritizing health equity, efforts can be made to achieve a more balanced approach to marijuana regulation that reduces risks while addressing structural disparities.