Thursday, April 15, 2021

Study Suggests Cannabis Use in Adolescence Leads to Poorer School Performance and Lower Socioeconomic Status

Minnesota Twin Family Study
A new University of Minnesota study authored by a team of researchers in the Department of Psychology and Institute of Child Development (ICD) suggests that cannabis use in adolescence leads to poorer school performance and lower socioeconomic attainment, but not higher rates of mental health or cognitive concerns in adulthood. The study was conducted with thousands of identical twins from the age of 11 into adulthood. The study was led by Jonathan Schaefer and the team included William Iacono, Stephen Malone, Matt McGue, Scott Vrieze, and Sylia Wilson.

The study examined pairs of identical twins in which one twin reported using more cannabis in adolescence than the other. Results indicated that the twin who used more cannabis as a teenager tended to perform worse in middle or high school. Also, in adulthood, they tended to report lower educational attainment, occupational status, and annual income. However, the twins were statistically comparable in terms of adult psychiatric diagnoses and scores on cognitive tests. The results suggest that actions and/or treatments aimed solely on reducing teen cannabis use without addressing other contextual issues are unlikely to generate long-term positive effects on cognitive functioning and mental health, but might reduce rates of educational and occupational underachievement in young adulthood.


The full research paper can be viewed on the Proceedings of the National Academy of Sciences of the United States of America’s website.



Composed by Flora Pollack, communications assistant.