WASHINGTON, Feb. 21 (Xinhua) -- A study found that frequent use of marijuana is closely associated with lower grades among students, U.S. media reported Thursday.
The study, released by University of Minnesota's (UM) Boynton Health, found that male students who have used marijuana in all 30 days prior to the survey had an average Grade Point Average (GPA) of 3.01, while those who did not smoke marijuana on average scored 3.33.
The numbers for female students were 3.18 and 3.4 respectively.
The research found that GPA difference between marijuana users and non users were much stronger than that of alcohol drinkers and non-drinkers, or between students of different ages.
The study did not establish a causal and effect link between using marijuana and lower grades, saying it could equally be possible that using marijuana lowers grades and that students with lower grades are more readily to use the substance.
The analysis is based on Boynton's survey of 10,579 students at the UM and 17 other schools in the state.
The study followed a 2018 survey by the same organization that found a significant increase in marijuana use among students.
While the state still bans recreational use of marijuana, the United States is becoming more tolerant of the use of the drug. Ten states have legalized recreational use of marijuana, and the U.S. media predicted that Minnesota is likely to become the next state lifting the ban.