Teen Use of Tobacco and Marijuana Affects School Attendance and Performance: Study

A new study finds high school students who use both tobacco and marijuana products miss more school and have lower grades than their peers who use one of these substances alone or neither.

Researchers from UC Davis Health evaluated 2021-22 data from the California Healthy Kids Survey, which included more than 287,6000 9th and 11th graders. Of that group, 7% used tobacco and marijuana; 3.7% used marijuana only; and 1.7% used tobacco only. Those who used both tobacco and marijuana missed an average three days of school in the preceding month — twice as many as teens who didn’t use both, HealthDay reports.

Using tobacco and marijuana was also associated with lower grades. Students who did not use marijuana or tobacco had mostly B’s, while those who used both marijuana and tobacco received mostly B- and C’s.

“Substance use is a main predictor of educational outcomes, including absenteeism,” study first author Melanie Dove said in a news release. “These results highlight the need for comprehensive efforts to prevent and reduce substance use from both cannabis and tobacco products among youth.”