As cannabis becomes legal in more U.S. states, more people seem to believe that smoking it is safe—especially compared to smoking tobacco. But is that belief backed by science?
A recent study published in JAMA Network Open shows that public opinion about the safety of cannabis smoke has shifted significantly in recent years, even though health experts warn that all smoke, whether from cannabis or tobacco, can be harmful to the lungs.
Between 2017 and 2021, the number of adults who thought daily cannabis smoking was safer than daily tobacco smoking rose from 37% to 44%. The same trend was seen for secondhand smoke, with 40% of people believing that cannabis secondhand smoke was less harmful than tobacco smoke.
Younger adults, especially those aged 18 to 29, were more likely to believe cannabis smoke was safer, while older adults—those 60 and over—were more cautious and believed the opposite. Factors like age, marital status, and employment seemed to influence these opinions.
So why do people think cannabis smoke is safer?
Experts say there are a few possible reasons. First, tobacco has been studied for decades. People have been exposed to clear and repeated warnings about its dangers, including strong anti-smoking campaigns, warning labels on cigarette packs, and strict public health policies.
In contrast, cannabis hasn’t been studied as much, partly because strict federal laws in the U.S. have made it hard for researchers to fully explore its health effects.
Second, cannabis is being legalized across more states for both medical and recreational use. While tobacco is being pushed out of public spaces and taxed heavily, cannabis is gaining acceptance. That contrast may send the wrong message—that cannabis is not just legal, but also safe.
Third, many people believe that cannabis has medical benefits. Indeed, some forms of cannabis are used to treat pain, anxiety, epilepsy, and other conditions. But that doesn’t mean that smoking cannabis every day is without risk.
Dr. Beth Cohen, from the University of California, San Francisco, was one of the researchers involved in the study. She points out that both cannabis and tobacco smoke contain toxins and cancer-causing chemicals.
Inhaling any kind of smoke—whether from a cigarette or a joint—introduces harmful particles deep into the lungs. Over time, this can cause inflammation and damage, possibly leading to breathing problems or heart disease.
Dr. Albert Rizzo from the American Lung Association agrees. He says just because cannabis is legal doesn’t mean it’s safe. Legalization is often based on political or social choices, not scientific proof.
He adds that it took many years and large studies before the public fully understood how dangerous tobacco really is. The same could be true for cannabis—its long-term effects may not be fully known yet.
Animal studies have already shown some worrying signs. Both cannabis and tobacco smoke can affect the heart and blood vessels. In people, some early research suggests that cannabis may increase the risk of heart attack, especially in young adults.
Experts believe that more education is needed. Public health officials should help young people and parents understand that smoking cannabis can carry serious risks—just like smoking cigarettes. While more research is still needed, what we already know should be enough to encourage caution.
In the end, the choice to use cannabis is personal. But that choice should be based on facts, not just changing laws or social trends. As cannabis use becomes more common, it’s important for everyone to understand the potential health risks so they can make informed decisions.
If you care about smoking, please read studies about smoking may increase heart disease risk by 200% and e-cigarette smoke may cause lung cancer and bladder disease.
For more health information, please see recent studies about the cause of weight gain after smoking cessation, and results showing smoking may cause white scars on the brain.
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