Young adults reported better sleep quality on days they used alcohol and cannabis together compared to alcohol-only or no-use days
In a daily diary study of 150 young adults, simultaneous alcohol-cannabis use days were associated with better sleep quality and longer sleep duration compared to alcohol-only days, and better sleep quality compared to no-use days.
Quick Facts
What This Study Found
Compared to simultaneous use days, participants reported worse sleep quality and shorter sleep on alcohol-only days, earlier bedtime on cannabis-only days, and poorer sleep quality on no-use days. Those with greater alcohol problem severity reported even more pronounced differences favoring simultaneous use days. Sleep did not predict next-day simultaneous use.
Key Numbers
150 participants, 64% female, mean age 22.09. Simultaneous use days had better sleep quality vs. alcohol-only and no-use days. Longer sleep duration vs. alcohol-only days.
How They Did This
Daily diary study of 150 young adults (64% female, mean age 22.09) completing morning smartphone surveys on prior-day substance use and previous-night sleep. Baseline alcohol and cannabis problem severity were measured. Within-person comparisons across day types.
Why This Research Matters
Many young adults use substances to manage sleep. This study shows the combination may produce subjectively better sleep than alcohol alone, which could reinforce simultaneous use patterns and escalate co-use over time.
The Bigger Picture
If people sleep better when combining substances, they may escalate to more frequent co-use, potentially increasing long-term dependency risks. This reinforcement mechanism is rarely discussed in substance use prevention.
What This Study Doesn't Tell Us
Self-reported sleep measures, no objective sleep data. Within-person design cannot establish causation. Young adult sample. No assessment of sleep architecture.
Questions This Raises
- ?Does subjectively better sleep on simultaneous use days reflect actual improvements in sleep architecture?
- ?Could this reinforcement pattern drive escalation of co-use?
Trust & Context
- Key Stat:
- Simultaneous use days had better sleep quality than alcohol-only, cannabis-only, and no-use days
- Evidence Grade:
- Well-designed daily diary study with within-person comparisons, but reliance on self-reported sleep limits conclusions.
- Study Age:
- 2026 publication
- Original Title:
- Smoke, sip, sleep, repeat: Investigating daily-level bidirectional relationships of separate and simultaneous use of alcohol and cannabis with sleep.
- Published In:
- Psychology of addictive behaviors : journal of the Society of Psychologists in Addictive Behaviors (2026)
- Authors:
- Moore, Annabelle, Coelho, Sophie G(2), Hendershot, Christian S(6), Wardell, Jeffrey D
- Database ID:
- RTHC-08503
Evidence Hierarchy
Follows a group of people over time to track how outcomes develop.
What do these levels mean? →Frequently Asked Questions
Does using alcohol and cannabis together actually improve sleep?
Participants reported better subjective sleep quality, but the study did not measure actual sleep stages objectively. Perceived sleep quality may differ from physiological sleep quality.
Could this lead to more substance use?
The study raises this concern. If people consistently sleep better when combining substances, it could reinforce the pattern over time.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-08503APA
Moore, Annabelle; Coelho, Sophie G; Hendershot, Christian S; Wardell, Jeffrey D. (2026). Smoke, sip, sleep, repeat: Investigating daily-level bidirectional relationships of separate and simultaneous use of alcohol and cannabis with sleep.. Psychology of addictive behaviors : journal of the Society of Psychologists in Addictive Behaviors. https://doi.org/10.1037/adb0001124
MLA
Moore, Annabelle, et al. "Smoke, sip, sleep, repeat: Investigating daily-level bidirectional relationships of separate and simultaneous use of alcohol and cannabis with sleep.." Psychology of addictive behaviors : journal of the Society of Psychologists in Addictive Behaviors, 2026. https://doi.org/10.1037/adb0001124
RethinkTHC
RethinkTHC Research Database. "Smoke, sip, sleep, repeat: Investigating daily-level bidirec..." RTHC-08503. Retrieved from https://rethinkthc.com/research/moore-2026-smoke-sip-sleep-repeat
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.