Three Distinct Daily Substance Use Patterns Emerge Among Young Adult Vapers

A 30-day daily diary study identified three patterns among young adults who vape: nicotine-only days (53%), nicotine-cannabis co-vaping days (40%), and combustible tobacco-cannabis days (7%), with sadness driving nicotine-only use and cannabis cravings driving co-use.

Halliday, Deanna M et al.·Drug and alcohol dependence·2026·Moderate Evidencelongitudinal
RTHC-08309LongitudinalModerate Evidence2026RETHINKTHC RESEARCH DATABASErethinkthc.com/research

Quick Facts

Study Type
longitudinal
Evidence
Moderate Evidence
Sample
N=113

What This Study Found

Three daily substance use classes emerged: nicotine vaping days (52.7%), nicotine+cannabis co-vaping days (39.9%), and combustible tobacco+cannabis days (7.4%), with sadness predicting nicotine-only days (aOR=1.11) and cannabis craving predicting co-vaping days (aOR=1.81).

Key Numbers

N=113; mean age 23.8; 30 consecutive days; Class 1 nicotine vaping 52.7%; Class 2 co-vaping 39.9%; Class 3 combustible+cannabis 7.4%; sadness→Class 1 aOR=1.11; cannabis craving→Class 2 aOR=1.81

How They Did This

30-day smartphone-based daily diary study of 113 California young adults (mean age 23.8) who vaped nicotine or cannabis 20+ days/month, using multilevel latent class analysis and mixed-effects logistic regression.

Why This Research Matters

Understanding daily substance use patterns reveals that vaping, cannabis, and combustible tobacco use are interconnected — interventions targeting one substance should consider these overlapping patterns.

The Bigger Picture

The high prevalence of co-vaping days (40%) among young adult vapers suggests that cannabis and nicotine use are deeply intertwined, and cessation programs may need to address both simultaneously.

What This Study Doesn't Tell Us

California-only sample; self-selected heavy vapers; 30-day window; self-report data; relatively small sample; cannot determine causal direction between mood and substance use; limited to young adults.

Questions This Raises

  • ?Would intervening on cannabis cravings reduce nicotine vaping too?
  • ?Are combustible tobacco days a marker of higher addiction severity?
  • ?How do these patterns change over months or years?

Trust & Context

Key Stat:
Evidence Grade:
Well-designed daily diary study with appropriate multilevel analysis, though limited by small California sample and self-report measures.
Study Age:
Published 2026; reflects current vaping patterns among young adults.
Original Title:
Daily patterns of substance use among young adults who vape nicotine and cannabis: Latent class analysis of smartphone-based daily diary data.
Published In:
Drug and alcohol dependence, 280, 113060 (2026)
Database ID:
RTHC-08309

Evidence Hierarchy

Meta-Analysis / Systematic Review
Randomized Controlled Trial
Cohort / Case-Control
Cross-Sectional / ObservationalSnapshot without intervening
This study
Case Report / Animal Study
What do these levels mean? →

Frequently Asked Questions

How common is vaping both nicotine and cannabis?

Very common — in this study of young adult vapers, nearly 40% of all days assessed involved vaping both nicotine and cannabis, making co-vaping almost as common as nicotine-only vaping days.

What drives people to vape cannabis with nicotine?

Cannabis cravings were the strongest predictor of co-vaping days (1.8x higher odds), while feeling sad was associated with nicotine-only vaping days, suggesting different emotional states drive different use patterns.

Read More on RethinkTHC

Cite This Study

RTHC-08309·https://rethinkthc.com/research/RTHC-08309

APA

Halliday, Deanna M; Lund, Lisbeth; Ling, Pamela M; Nguyen, Nhung. (2026). Daily patterns of substance use among young adults who vape nicotine and cannabis: Latent class analysis of smartphone-based daily diary data.. Drug and alcohol dependence, 280, 113060. https://doi.org/10.1016/j.drugalcdep.2026.113060

MLA

Halliday, Deanna M, et al. "Daily patterns of substance use among young adults who vape nicotine and cannabis: Latent class analysis of smartphone-based daily diary data.." Drug and alcohol dependence, 2026. https://doi.org/10.1016/j.drugalcdep.2026.113060

RethinkTHC

RethinkTHC Research Database. "Daily patterns of substance use among young adults who vape ..." RTHC-08309. Retrieved from https://rethinkthc.com/research/halliday-2026-daily-patterns-of-substance

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.