California youth consistently perceive marijuana to be less harmful than other commonly used substances, according to a new study that analyzed data from two large statewide school surveys. Dr. Xu Hong Zhu, from the Herbert Wertheim School of Public Health and Human Longevity Sciences at the University of California, San Diego, and her co-authors investigated how teens view the risks of regular and occasional use of cannabis compared to alcohol, nicotine e-cigarettes, and cigarettes, based on responses from more than 175,000 students across surveys conducted in 2019-2020 and 2024.
The findings show a clear and persistent pattern. Cannabis is considered the least harmful substance among respondents. Previous research found that around two-thirds of adolescents thought regular cannabis use was harmful, compared with higher rates for alcohol, e-cigarettes, and cigarettes. Perceptions of harm were low for all occasionally used substances, but cannabis remained the least likely to be of concern to teens. These trends remain stable in the 2024 data, suggesting that adolescents’ perceptions of cannabis-related risks are relatively low and consistent over time.
The study also identified important differences based on age, experience, and social environment. Unlike alcohol and tobacco products, where perceived harm generally remains the same or increases with grade level, perceptions of the risks of cannabis decreased as students got older. Young adolescents were more likely to think of cannabis as harmful, but this perception weakened significantly by 12th grade. Additionally, teens who used a substance were less likely to think it was harmful, with the largest gap in perception occurring for cannabis. Peer influence played a big role as well. Adolescents who had more friends who used a substance consistently rated the substance as less harmful, again with cannabis having the strongest effect.
These findings raise public health concerns because the lower the perceived risk, the more likely it is to be used. Although marijuana use among adolescents has declined overall in recent years, researchers say it remains a concern because of its potential effects on brain development, cognition and mental health. The authors suggest that prevention and education efforts may need to better address the unique risks of cannabis, especially as changing social norms and increased exposure to pro-cannabis messages may be influencing young people’s perceptions of safety.
This study was published on May 5, 2026. drug and alcohol addiction.
sauce:
University of California San Diego
Reference magazines:
Agarwal, D. others. (2026). Adolescents think marijuana is less harmful than cigarettes, nicotine e-cigarettes, and alcohol: Results from two California school surveys. Drug and alcohol dependence. DOI: 10.1016/j.drugalcdep.2026.113155. https://www.sciencedirect.com/science/article/pii/S0376871626001365

