Three Distinct Daily Substance Use Patterns Emerge Among Young Adult Vapers | Research

The takeaway

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.

Vaping cessation counselors, young adult health professionals, addiction researchers, and policy makers addressing nicotine-cannabis co-use.

What the researchers 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).

Why it 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 numbers in context

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 the study worked

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.

What this study cannot 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.

How to read the evidence

Well-designed daily diary study with appropriate multilevel analysis, though limited by small California sample and self-report measures.

When this study was published

Published 2026; reflects current vaping patterns among young adults.

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.

Questions still open

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?

Common 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 the original research

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

View on PubMed ↗Publisher’s paper ↗

Citation

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