Press Releases

2000 Releases

Survey Finds Increased Use of Marijuana and Other Illicit Drugs at U.S. Colleges in the 1990s

For immediate release: October 27, 2000

BOSTON, MA--According to a new report from Harvard School of Public Health researchers, the prevalence of recent marijuana use among U.S. college students rose from 12.9% to 15.7% between 1993 and 1999, an increase of 22%. Most of the increase occurred between 1993 and 1997. While rates did not increase further in 1999, they did remain at the higher 1997 rate. Use of other illicit drugs followed the same trend, rising significantly between 1993 and 1997, then changing little between 1997 and 1999.

The trends were drawn from lifestyle survey data collected as part of the Harvard School of Public Health's College Alcohol Study. Henry Wechsler, PhD, Director of the College Alcohol Study, and Jeana Gledhill-Hoyt, lead author of the marijuana report, found that the increase was widespread, observed at two-thirds (66%) of the 119 colleges. Between 1993 and 1999, marijuana use had increased among most demographic groups of American college students and at almost all types of colleges, public and private, large and small, urban and suburban, indicating a strong national pattern. 

The report was based on the responses of more than 14,000 students selected randomly each year in 1993, 1997, and 1999 from 119 four-year colleges in 40 states. The study was funded under a grant from the Robert Wood Johnson Foundation and appears in the November 2000 issue of Addiction.

These findings are in line with those reported elsewhere in studies of middle school and high school students. The National Institute of Health's Monitoring the Future Study found that there were elevated rates of marijuana and other illicit drug use in these populations in the early 1990s. The increased college rates found in the present study may reflect the group effect of high school drug users enrolling in college. In contrast, drug use in the 1960s often started on college campuses and trickled down to younger high school and junior high school populations.

According to Wechsler, "These new findings should be a source of concern for those involved with the prevention and treatment of illicit drug use among young people. Although rates of drug use stabilized at the end of the decade, no significant decreases have yet been observed. Prevention efforts aimed at illicit drug use should be stepped up and tied to those already in place for binge drinking and cigarette use. Results of this study demonstrate the need for drug abuse prevention programs in the secondary schools, as well as in college to prevent experimental illicit drug users from becoming regular users." 

Authors of the study are: Jeana Gledhill-Hoyt, MPH, Hang Lee, PhD, Jared Strote, MD and Henry Wechsler, PhD. Additional information on the Harvard School of Public Health College Alcohol Study can be found at:

For further information, please contact:

Robin Herman
Office of Communications
Harvard School of Public Health
677 Huntington Avenue
Boston, MA 02115
Phone: 617-432-4752