Marijuana has quietly become a surprisingly common tool among Americans trying to quit cigarettes, according to new research finding that cannabis is being used for smoking cessation almost as frequently as prescription quit-smoking medications. In a survey of 2,804 U.S. adults who smoked cigarettes, used nicotine e-cigarettes or used both, 9 percent of people attempting to stop smoking cigarettes reported using cannabis as a cessation aid. Prescription medications were used by 9.4 percent—placing the two approaches remarkably close despite the enormous difference in scientific evidence supporting them.
The study, published October 13, 2026 in the Journal of General Internal Medicine, was conducted by Deanna Halliday and colleagues from the University of California, San Francisco, the San Francisco VA Health Care System, New York University and collaborating institutions. THC-containing cannabis products accounted for most of the marijuana being used during quit attempts. The findings reveal an important shift in smoking-cessation behavior as marijuana becomes more accessible across the United States, but they do not demonstrate that cannabis actually helps people quit cigarettes. In fact, other recent research suggests regular cannabis co-use may make successful tobacco cessation more difficult.
Cannabis Has Become a Mainstream Quit-Smoking Strategy
The near tie between marijuana and prescription medications is striking because cannabis is not approved as a tobacco-cessation treatment. Medications such as varenicline and sustained-release bupropion have undergone randomized clinical trials specifically designed to measure whether they improve long-term cigarette abstinence. Cannabis products sold through state marijuana markets generally have not been evaluated under anything approaching the same clinical standard.
Yet the new survey found cannabis use during cigarette quit attempts was nearly as common as prescription pharmacotherapy. Researchers described THC as a popular cessation aid whose use exceeded several evidence-based approaches. Cannabis was also more commonly reported than behavioral health interventions among people trying to stop cigarettes or nicotine vaping. That suggests many consumers are developing their own cessation strategies outside conventional healthcare, potentially based on personal experience, advice from friends, online information or the belief that marijuana can replace some of the effects or rituals associated with tobacco.
The pattern extended beyond traditional cigarettes. Among participants trying to quit nicotine vaping, cannabis was the third most commonly reported cessation approach, behind quitting without assistance and using another recreational nicotine product. THC-containing products again accounted for most cannabis use, showing that people were not primarily turning to nonintoxicating CBD supplements.
The Study Measures Popularity, Not Whether Marijuana Works
The most important limitation of the research is straightforward: it measured what people were using to try to quit nicotine, not whether those methods actually enabled them to remain tobacco-free. Someone reporting cannabis as a cessation aid may have successfully stopped smoking cigarettes, may have reduced cigarette consumption without quitting, or may have relapsed completely. Those outcomes are fundamentally different, and the new survey was not a randomized comparison of cannabis against varenicline, nicotine replacement or placebo.
That distinction becomes particularly important because the 9 percent and 9.4 percent figures can easily be misinterpreted. Cannabis being almost as popular as prescription drugs does not mean it is almost as effective. Prescription cessation medications have decades of controlled clinical evidence supporting their effectiveness. Cannabis currently has no comparable body of randomized trials showing that THC-containing marijuana products produce durable cigarette abstinence.
The study is therefore most significant as evidence of real-world behavior. Millions of people continue trying to stop smoking, and a substantial group appears to be experimenting with cannabis despite the absence of established clinical guidance. For physicians and smoking-cessation specialists, asking patients about marijuana may consequently become increasingly important when discussing quit attempts.
THC Users Reported More Severe Nicotine Withdrawal Symptoms
The survey produced another finding that complicates the idea of marijuana as an easy way through nicotine withdrawal. Participants who used THC products while trying to stop smoking reported greater severity of several nicotine-withdrawal symptoms, including feeling upset, restlessness, difficulty concentrating, troubled sleep and increased thoughts about food. People using THC while attempting to quit nicotine vaping also reported greater difficulty concentrating.
Those findings do not necessarily mean THC caused the symptoms. People experiencing the most severe withdrawal may have been particularly likely to reach for cannabis in an attempt to manage their discomfort. Someone struggling with irritability or insomnia, for example, could decide to use marijuana precisely because those symptoms are already severe. A cross-sectional survey cannot fully determine which came first.
Nevertheless, the results challenge the assumption that THC reliably suppresses nicotine withdrawal in humans. Some users may perceive cannabis as calming or sleep-promoting, but THC can also produce anxiety, impaired concentration, altered sleep architecture and other effects that overlap with nicotine withdrawal. Using the two substances together can make it difficult to determine whether a symptom comes from stopping nicotine, using cannabis or both.
New Meta-Analysis Finds Cannabis Co-Use May Reduce Quit Success
The new cessation-aid survey arrives almost simultaneously with a major 2026 systematic review examining the broader relationship between cannabis and tobacco use disorder. Researchers led by Gabriel Costa, Joao De Aquino and colleagues reviewed 52 studies spanning observational human research, animal experiments and experimental cannabinoid studies. Their final meta-analysis included 18 observational studies representing more than 229,000 participants.
The analysis found cannabis use was associated with approximately 25 percent lower odds of successfully quitting tobacco. The result does not prove marijuana prevents cessation because cannabis users and nonusers may differ in nicotine dependence, age, alcohol use, mental health and other factors. Still, the size and consistency of the overall signal raise concern that ordinary cannabis co-use is not functioning as an effective smoking-cessation treatment for most people.
The same review produced an important scientific distinction. Naturalistic cannabis co-use appeared associated with poorer tobacco outcomes, yet manipulating specific components of the endocannabinoid system showed therapeutic potential in laboratory studies. CBD, in particular, demonstrated signals suggesting it might influence nicotine reinforcement and withdrawal differently from THC-dominant marijuana. Treating “cannabis” as one drug may therefore obscure major differences among cannabinoids.
Prospective Treatment Research Also Raises Concerns About Co-Use
Another 2026 study published in Addiction directly followed adults receiving evidence-based tobacco treatment. Erin McClure and colleagues enrolled 181 participants between ages 18 and 40 at three South Carolina research sites. Of those participants, 110 regularly used both cigarettes and cannabis while 71 smoked cigarettes without regular cannabis use. Everyone received 12 weeks of varenicline, counseling and financial incentives for tobacco abstinence.
At the end of treatment, 59 percent of participants in the tobacco-only group achieved biochemically confirmed seven-day cigarette abstinence, compared with 33 percent of those who regularly used cannabis. The study was not randomized according to cannabis use, so it cannot prove cannabis itself caused the difference. However, it provides stronger prospective evidence than a simple cross-sectional survey because researchers followed participants through the same structured cessation program.
Interestingly, cannabis-use frequency within the co-use group was not clearly associated with abstinence after adjustment. That suggests the relationship may involve more than simply “more cannabis equals less quitting.” Behavioral routines, social environments, shared smoking cues or characteristics of people who use both substances may contribute to the lower cessation rate.
Smoking Cannabis and Tobacco Can Reinforce the Same Behavioral Cues
Nicotine dependence is not driven solely by pharmacology. Cigarette smoking becomes connected with hundreds of repeated behaviors: holding something between the fingers, inhaling smoke, stepping outside, taking breaks, socializing and responding to stress. Cannabis smoked in joints, pipes or blunts can preserve many of those same sensory and behavioral patterns even when nicotine is removed.
Research from the International Tobacco Control Four Country Smoking and Vaping Survey has provided evidence that increasing cannabis use can accompany poorer cigarette-cessation outcomes. Among thousands of smokers in the United States, Canada, England and Australia, people who increased cannabis use were less likely to quit cigarettes and less likely to maintain abstinence for at least six months. Those who reduced or stopped cannabis use showed better cigarette-cessation rates.
Smoking cannabis together with tobacco may be particularly problematic. In the same international dataset, people who smoked cannabis mixed with tobacco had much lower rates of cigarette cessation than several other groups. The behavioral connection is obvious: tobacco remains embedded directly inside the cannabis ritual, continually exposing the user to nicotine and maintaining cues associated with smoking.
Some People May Successfully Substitute Cannabis for Nicotine
The research is not entirely negative. A separate analysis of the long-running Population Assessment of Tobacco and Health study examined more than 8,000 adults who initially used nicotine but not cannabis. Most continued using nicotine, while smaller groups transitioned to cannabis-nicotine co-use, stopped both substances or moved from nicotine to cannabis alone.
People who began co-using cannabis and nicotine had lower subsequent nicotine-abstinence rates than adults who continued exclusively using nicotine. But the very small group that completely switched from nicotine to cannabis showed high rates of later nicotine abstinence. Approximately 72 percent of those who transitioned to exclusive cannabis use were nicotine-abstinent at follow-up, compared with about 10 percent among people who continued exclusive nicotine use.
That finding should be interpreted cautiously. Only about 1 percent of the population made the complete transition to cannabis, and researchers did not randomly assign people to substitute marijuana for nicotine. Individuals capable of completely replacing cigarettes with another substance may differ significantly from those who continue using both. Still, the study raises an important harm-reduction question: cannabis co-use and complete cannabis substitution may produce very different outcomes.
CBD Has Produced a Small but Intriguing Smoking-Cessation Signal
THC-dominant marijuana should also be distinguished from cannabidiol. One of the most frequently cited cannabinoid studies in tobacco research was a 2013 randomized, double-blind pilot trial conducted by Celia Morgan and colleagues at University College London. Twenty-four smokers who wanted to stop smoking received either a CBD inhaler or placebo and were told to use it whenever they felt the urge to smoke.
During the one-week experiment, cigarette consumption fell by approximately 40 percent among participants using CBD, while the placebo group showed no comparable reduction. Some of the effect appeared to persist during short-term follow-up. The study was extremely small, however, and reducing cigarettes over seven days is not equivalent to achieving long-term tobacco abstinence.
Subsequent experimental research has suggested CBD may reduce attention to cigarette-related cues and influence withdrawal-related processes, providing a plausible reason for larger clinical trials. The new 2026 systematic review concluded that CBD remains promising enough to investigate further. That does not provide evidence that dispensary marijuana containing substantial THC should be recommended for smoking cessation.
Proven Quit-Smoking Treatments Remain Much Better Studied
Seven FDA-approved medications are currently available to help adults stop smoking cigarettes. Five involve nicotine replacement—the patch, gum, lozenge, nasal spray and oral inhaler—while varenicline and bupropion SR are prescription tablets that do not simply replace cigarettes with another smoked product.
Large systematic reviews consistently show these treatments improve the likelihood of quitting compared with placebo or trying without medication. A major Cochrane review found that for every 100 people using varenicline, approximately 21 to 25 could be expected to stop smoking for at least six months, compared with roughly 18 using bupropion or a single form of nicotine replacement therapy. Combining nicotine-replacement products, such as a patch with gum or lozenges, can also improve results compared with using a single nicotine product.
Behavioral support adds another layer of effectiveness. Counseling helps people identify triggers, develop strategies for cravings and manage relapse risk, while medication reduces the biological pressure created by nicotine dependence. The fact that the new survey found marijuana use exceeding some behavioral interventions therefore highlights a disconnect between which strategies have strong evidence and which strategies some smokers are actually choosing.
Marijuana’s Appeal as a Cigarette Substitute Is Easy to Understand
Despite the scientific uncertainty, there are understandable reasons someone might use marijuana while stopping cigarettes. THC can produce relaxation and distraction from cravings, change mood and appetite and provide another ritual during periods previously associated with smoking. For people living in legal cannabis states, obtaining marijuana may also be easier than arranging a medical appointment for a prescription medication.
Cannabis legalization has occurred at the same time cigarette smoking has fallen to historic lows. Gallup reported in 2026 that 17 percent of U.S. adults said they smoke marijuana while only 11 percent reported smoking cigarettes. That does not mean marijuana caused the decline in tobacco use, but it reflects a profound shift in the relative social acceptance and availability of the two substances.
The substitution concept extends beyond tobacco. Surveys increasingly find people reporting cannabis use in place of alcohol, sleep medications, pain medications and other substances. Whether those substitutions reduce overall health risk depends heavily on the original substance, the cannabis product, dose, frequency and route of administration.
Replacing Cigarette Smoke With Cannabis Smoke Is Not Risk-Free
Smoking fewer tobacco cigarettes can substantially reduce exposure to tobacco combustion products, but replacing them with smoked cannabis does not eliminate respiratory exposure. Burning plant material generates particulate matter, carbon monoxide and numerous irritant and toxic compounds regardless of whether the plant is tobacco or cannabis. Cannabis smoke and tobacco smoke are chemically different in important ways, but neither is simply clean air.
The American Thoracic Society’s 2025 research statement on tobacco and cannabis co-use concluded that the existing evidence on cessation is mixed but increasingly suggests cannabis can interfere with tobacco abstinence in some populations. The organization also emphasized the need to study route of administration more carefully because smoking cannabis, vaping THC and consuming non-inhaled products create very different respiratory exposures.
There is also the possibility of replacing one dependence problem with another. Frequent THC use can produce tolerance, withdrawal and cannabis use disorder in a subset of users. A smoking-cessation strategy should therefore be evaluated not only by whether cigarette consumption falls, but by what happens to total substance use, health and dependence afterward.
The New Study Exposes a Major Gap in Cannabis Research
The most important conclusion from Halliday and colleagues’ study may be that cannabis is already functioning as a de facto smoking-cessation product whether medical guidelines acknowledge it or not. Nine percent of cigarette quitters reporting cannabis use is too large a group to treat as a fringe phenomenon, particularly when prescription smoking-cessation medication use was only slightly higher at 9.4 percent.
Researchers now need controlled trials that distinguish THC from CBD, smoked products from non-inhaled formulations and occasional substitution from sustained cannabis use. Studies also need to measure actual cigarette abstinence rather than simply reductions in daily smoking, while following participants long enough to determine whether cannabis use persists or evolves into problematic use.
For now, marijuana’s popularity as a quit-smoking tool has moved well ahead of the evidence supporting it. Some observational research suggests complete substitution could help certain people leave nicotine behind, and CBD has produced intriguing early results. At the same time, a growing body of research finds that people who continue using cannabis alongside cigarettes are less likely to successfully quit tobacco. The new national survey therefore reveals something important without resolving the central question: Americans are already experimenting with cannabis as a nicotine-cessation aid on a large scale, and science now has to determine whether that strategy represents effective harm reduction, an ineffective workaround or simply the exchange of one dependence for another.
