Teenagers and Young Adults Who Use Cannabis Have a Higher Risk of Progressing to Regular Tobacco Use

Although tobacco use among teens and young adults has declined considerably in the United States since the 1970s, cannabis use has not. This raises the question of whether a reverse gateway from cannabis to regular tobacco use might exist.

To investigate, the authors mined data from a regular survey of U.S. households called PATH (Population Assessment of Tobacco and Health) to look at the association of cannabis use by teens and young adults in 2017 and their likelihood of regular tobacco use four years later in 2021.

A total of 13,851 respondents aged 12–24 years were identified who, in 2017, reported never or not regularly using any form of tobacco (combustible or non-combustible) and who completed subsequent surveys. Among these respondents, 15.4% reported using cannabis within the past 12 months. The likelihood of cannabis use increased with age.

Each person who used cannabis was matched to a similar non-user according to a number of characteristics including demographics, history of experimentation with tobacco products, perceived harmfulness of cigarettes and mental health symptoms.

The study found that 32.7% of U.S. teens aged 12–17 years who had used cannabis had progressed to regular tobacco use four years later — 15.6 percentage points higher than their matched controls. Among the young adults aged 18–24 years, 14.0% of those who used cannabis reported regular tobacco use — 5.4 percentage points higher than their matched controls.

The analysis attributed 13.0% of total new regular tobacco use to cannabis and when extrapolated across the entire U.S. population, the authors estimated that 509,800 fewer U.S. teens and young adults would have progressed to regular tobacco use in 2021 if they had not had previous experience of cannabis in 2017.

This is an observational study, and as such, can’t establish cause and effect, and the authors also acknowledge several limitations including the use of self-reported measures for tobacco and cannabis use. Although a comprehensive list of baseline characteristics was considered, some factors such as peer influences, socioeconomic factors and an underlying liability to substance use may not have been captured fully. Assessing cannabis use in the past 12 months rather than current use is also likely to have weakened the measured association.

Nevertheless, the authors conclude that cannabis use by U.S. youth is a major risk factor for progression to regular tobacco use and that cannabis prevention should be included as a key goal in tobacco control programs.

Because major health agencies have not yet addressed the potential of early cannabis use to increase future tobacco use, the researchers also suggest that failure to address cannabis use among young people has the potential to undermine the progress tobacco control efforts have made in reducing tobacco initiation and progression to regular use.

Link to full study.

Additional coauthors on the study include Jiayu Chen, John P. Pierce, David R. Strong, Natalie E. Quach, Yuyan Shi, Sara B. McMenamin, Thet N.M. Khin, Matthew D. Stone, and Dennis R. Trinidad, all at the UC San Diego Herbert Wertheim School of Public Health and Human Longevity Science.

This study was funded, in part, by the Tobacco-Related Disease Research Program (TRDRP) of the University of California, Office of the President and the National Cancer Institute of the National Institutes of Health.

Declarations: The authors declare no conflicts of interest.