A new study from NYU Grossman School of Medicine and Columbia University found a small increase in problematic marijuana use among adolescents and adults age 26 and older in 4 states where recreational use of marijuana is legal.

Magdalena Cerdá, DrPH, director of the Center for Opioid Epidemiology and Policy and associate professor in the Department of Population Health at NYU Langone, and colleagues are the first to investigate the impact of marijuana legalization across multiple age groups in legal states.

“This is a really important piece in helping us understand how to legalize in a way that puts systems in place that will deal with the prevention and treatment of marijuana use disorder,” Dr. Cerdá tells Reuters.

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