Marijuana use peaked in April and December among young adults, regardless of college status
Monthly surveys of 761 young adults over 24 months found alcohol and marijuana use varied by calendar month, with marijuana use highest in April and December across all educational groups.
Quick Facts
What This Study Found
All substance use measures showed calendar month variation. Marijuana use was highest in April and December regardless of educational status. Alcohol use peaked in summer, October, and December. College students drank more per week overall, with the gap widest in September-October, but drinking levels converged across educational groups in summer and December.
Key Numbers
761 participants; 57% female; ages 18-23; 24 monthly surveys; marijuana use highest in April and December; alcohol peaked in summer, October, and December; 4-year college students drank more per week; drinking converged across groups in summer and December
How They Did This
Longitudinal study of 761 community-based young adults (57% female, ages 18-23 at enrollment) surveyed monthly for 24 consecutive months. Multilevel models accounted for nesting of monthly data within individuals. Compared patterns across educational status groups.
Why This Research Matters
Knowing when substance use peaks can help prevention programs time their efforts. The April marijuana peak (coinciding with cannabis culture's "4/20") and December holiday peak suggest cultural and social drivers of use patterns.
The Bigger Picture
Seasonal patterns in substance use reflect social, cultural, and academic influences. Understanding these patterns enables more precise targeting of prevention resources rather than spreading them evenly across the year.
What This Study Doesn't Tell Us
Community sample from one metropolitan area. Self-reported monthly use may not capture within-month variation. 24-month window limits ability to separate year effects from month effects. Cannot determine whether April peak is related to 4/20 specifically.
Questions This Raises
- ?Is the April marijuana peak driven by 4/20 celebrations specifically?
- ?Would prevention messaging timed to precede high-use months be more effective than year-round campaigns?
Trust & Context
- Key Stat:
- Marijuana use peaked in April and December across all educational groups
- Evidence Grade:
- Strong longitudinal design with monthly measurements over 24 months in a diverse sample, though limited to one geographic area.
- Study Age:
- Published in 2021.
- Original Title:
- Calendar Month Variation in Alcohol and Marijuana Use in a Community Sample of Young Adults.
- Published In:
- Journal of studies on alcohol and drugs, 82(2), 169-177 (2021)
- Authors:
- Fleming, Charles B(7), Duckworth, Jennifer C(2), Patrick, Megan E(8), Fairlie, Anne M, Abdallah, Devon A, Lee, Christine M
- Database ID:
- RTHC-03134
Evidence Hierarchy
Follows a group of people over time to track how outcomes develop.
What do these levels mean? →Frequently Asked Questions
When do young adults use marijuana most?
April and December showed the highest marijuana use across all educational groups. The April peak likely reflects cultural cannabis celebrations (4/20), while December coincides with holiday socializing.
Did college students use more marijuana?
For alcohol, college students clearly drank more per week. For marijuana, the calendar patterns were consistent across educational status groups, suggesting marijuana use calendars are driven more by cultural factors than academic ones.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-03134APA
Fleming, Charles B; Duckworth, Jennifer C; Patrick, Megan E; Fairlie, Anne M; Abdallah, Devon A; Lee, Christine M. (2021). Calendar Month Variation in Alcohol and Marijuana Use in a Community Sample of Young Adults.. Journal of studies on alcohol and drugs, 82(2), 169-177.
MLA
Fleming, Charles B, et al. "Calendar Month Variation in Alcohol and Marijuana Use in a Community Sample of Young Adults.." Journal of studies on alcohol and drugs, 2021.
RethinkTHC
RethinkTHC Research Database. "Calendar Month Variation in Alcohol and Marijuana Use in a C..." RTHC-03134. Retrieved from https://rethinkthc.com/research/fleming-2021-calendar-month-variation-in
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.