The number of Americans using both cannabis and tobacco is increasing, with a particular surge among older adults, a new study finds.
Researchers at Duke University School of Medicine who analyzed two decades of national data warn that the combination poses greater health risks than the dangers of using either substance alone.
In 2021, 6.38% of U.S. adults reported using both cannabis and tobacco within the past month. While this might seem like a relatively small percentage, it’s a big jump from previous years. Researchers attribute the trend to more states legalizing marijuana, and people becoming more accepting of and comfortable with cannabis.
“When looking at the 2021 data, younger individuals, people with lower educational attainment and residing in a state with a medical marijuana law, were most likely to report co-use,” said lead study author Dana Rubenstein, a fourth-year medical student at the Duke University School of Medicine and translational science researcher.
“Trends in cannabis and tobacco co-use prevalence have not been examined in many years while regulatory policy has been changing quite a bit,” she said.
Before the Duke analysis, the most recent report on trends in exclusive tobacco use, exclusive cannabis use, and co-use relied on national data from 2003-2012. Since that time 24 states have lifted restrictions on marijuana use, and now most Americans live in a state where recreational marijuana is legal.
The Aug. 13 study in Addictive Behaviors analyzed data on 708,891 adults from the 2002-2021 National Survey on Drug Use and Health and revealed key trends: From 2002 to 2019, co-use of cannabis and tobacco increased. Exclusive cannabis use rose after 2007, while exclusive tobacco use declined during the same period.
While most groups experienced a rise in co-use of cannabis and tobacco, young adults aged 18-25 bucked the trend, with co-use declining after 2014.
Rubenstein said one potential reason for the decline in co-use in this age group is that over the past two decades fewer young adults are using tobacco.
Dangerous New Normal?
This decrease in co-use contrasts sharply with the behavior of older age groups where co-use has been on the rise.
A dramatic rise was observed among individuals aged 50 and older whose co-use surged from a mere 0.42% in 2002 to 3.13% in 2019.
For those aged 26-34, co-use nearly doubled over the same period, jumping from 6.15% in 2002 to 10.3% in 2019. Similarly, adults aged 35-49 experienced a stable period from 2002-2009, followed by a notable increase, reaching 6.62% in 2019.
“As cannabis becomes more accessible due to legalization, we need to pay closer attention to the combined use of cannabis and tobacco, which poses unique health risks,” said Rubenstein, including exposure to cancer-causing chemicals and poorer cessation outcomes.
The trend suggests that health care providers should routinely screen for co-use when a patient reports using either tobacco or cannabis.
Study authors who include F. Joseph McClernon, PhD, and Lauren R. Pacek, PhD, formerly of Duke, urge the development of targeted programs to help people quit both substances and stresses the need to distinguish reasons for cannabis use – for medical relief or recreation – and how this affects co-use with tobacco.
The study was funded by the National Institutes of Health National Center for Advancing Translational Sciences TL1TR002555.