Among 467 regular users, people who smoked both tobacco and marijuana had fewer pack-years and smoked fewer cigarettes per day than tobacco-only smokers.
What the researchers found
Researchers analyzed smoking patterns in 467 people who regularly used tobacco, marijuana, or both. The goal was to understand how concurrent use of both substances related to tobacco consumption patterns.
People who smoked both tobacco and marijuana tended to have lower cumulative tobacco exposure, measured in pack-years. They also reported smoking fewer cigarettes per day compared to those who only smoked tobacco.
Across the sample, smoking habits either decreased or remained stable over the observation period, suggesting that adding marijuana to a tobacco habit did not accelerate cigarette consumption.
Why it matters
Understanding how tobacco and marijuana smoking habits interact is relevant for public health, particularly as marijuana legalization expands. If marijuana use is associated with lower tobacco consumption, that complicates simple assumptions about dual use being universally more harmful to the lungs.
The numbers in context
467 regular tobacco and marijuana users were analyzed. Dual users had fewer pack-years and fewer cigarettes per day than tobacco-only smokers. Smoking habits decreased or remained stable over time.
How the study worked
This cross-sectional study surveyed 467 regular tobacco and marijuana smokers, collecting data on daily cigarette counts, pack-years of tobacco exposure, and patterns of concurrent use. Researchers compared smoking characteristics between dual users and tobacco-only smokers.
What this study cannot tell us
As a cross-sectional study, this cannot determine whether marijuana use caused people to smoke fewer cigarettes or whether lighter tobacco smokers were simply more likely to also use marijuana. Self-reported smoking data is subject to recall bias. The study predates modern vaping and high-potency cannabis products.
How to read the evidence
A cross-sectional survey that identifies associations but cannot establish whether marijuana use caused lower tobacco consumption.
The bigger picture
This study contributed to the ongoing discussion about whether marijuana and tobacco use are synergistic or substitutive. Later research would continue to explore whether cannabis access reduces tobacco consumption at the population level, a question with significant public health implications.
Common questions
Did smoking marijuana make people smoke fewer cigarettes?
Does this mean smoking both is safer than just tobacco?
Read the original research
The relationship of tobacco and marijuana smoking characteristics.
Life sciences, 56(23-24), 2185-91
Citation
Simmons, M S; Tashkin, D P. (1995). The relationship of tobacco and marijuana smoking characteristics.. Life sciences, 56(23-24), 2185-91.