Study finds many Americans mistakenly believe exposure to marijuana smoke is less dangerous than tobacco
Is inhaling cannabis smoke safer than inhaling tobacco smoke? A majority of American adults say yes, according to a new survey, and they also believe that second-hand cannabis smoke is less harmful to adults and children than tobacco smoke.
A growing percentage of Americans consider smoking cannabis to be less dangerous than smoking tobacco cigarettes. They're right, but you wouldn't realize that from reading the recent spate of headlines in the media.
“Many Americans mistakenly believe that exposure to marijuana smoke is less dangerous than tobacco smoke,” exclaimed CNN. Everyday Health's coverage of the survey data warned, "People are underestimating the health risks of smoking marijuana." The coverage of the study by US News and World Report also lamented: More Americans than ever think marijuana smoke is less dangerous than cigarette smoke. They are wrong.
In fact, the media are wrong.
Numerous studies evaluating the long-term health effects of exposure to cannabis smoke disprove the myth that marijuana is associated with the same type of well-established adverse respiratory risks as tobacco.
For example, federally funded research by scientists at the University of California, Los Angeles compared the lifetime lung cancer risk of more than 2000 long-term marijuana smokers, smokers tobacco and non-smokers. Researchers determined that those who regularly smoked cigarettes had a 20 times greater risk of lung cancer than non-smokers. In contrast, those who only smoked marijuana did not have such a high risk.
"We hypothesized that there would be a positive association between marijuana use and lung cancer, and that this association would be more positive the higher the use was," explained the study's lead author. .
“What we found was that there was no association at all, and there was even a suggestion of a protective effect.
Another longitudinal study, conducted by researchers at the Colorado School of Public Health, assessed the relationship between lifetime marijuana use and lung function in a cohort of 2 subjects between the ages of 300 and 40. The study authors concluded, “Marijuana smokers and former smokers had significantly higher FEV (forced expiratory volume) higher than people who have never used marijuana…Current and past marijuana use was associated with significantly less quantitative emphysema than in people who had never used marijuana… In agreement with other published studies, we also did not find that marijuana use was associated with more lung disease obstructive.
More recently, a team of health experts wrote in May in the journal Chronic Obstructive Pulmonary Diseases that neither past nor current cannabis use was associated with evidence of chronic obstructive pulmonary disease (COPD) progression or development. They concluded: In this cohort of tobacco smokers ≥20 pack-years with established COPD or at risk of developing COPD, followed on average for more than four years, history of current and/or past marijuana use , regardless of the cumulative amount over a lifetime, were not associated with a significantly deleterious impact on the course of chronic obstructive pulmonary disease.
Other studies indicate that cannabis smoke and tobacco smoke are not equally carcinogenic and that subjects who exclusively smoke cannabis are less exposed to harmful toxicants and carcinogens than those who smoke tobacco cigarettes. Some researchers have also speculated that the anti-cancer activities of cannabinoids may offset some of the adverse effects associated with inhaling tobacco smoke.
According to data from a longitudinal study published last year in the American Journal of Respiratory and Critical Care Medicine, it is increasingly clear that cannabis has different effects on lung function compared to tobacco and that the effects of widespread cannabis use will not necessarily mirror the harm caused by smoking.
Another review article, published in November by a team of researchers affiliated with the University of Arkansas, is even more direct. "Marijuana data stand in stark contrast to the consistent demonstration of harm from tobacco, the biggest legalized killer in the world today," they conclude. “Any potential toxicity from marijuana pales in comparison.
This does not mean that exposure to cannabis smoke is completely harmless.
The smoke of cannabis contains some of the same toxins and particles as tobacco smoke, and some studies have linked smoking marijuana to temporary increases in sputum production and wheezing, as well as an increased risk of bronchitis. That said, exposure to combustible toxins can be greatly reduced by using a vaporizer that activates cannabinoids but does not heat them to the point of burning them. Laboratory studies have shown that herbal cannabis vaporizers are an “effective and apparently safe vehicle for the delivery of THC… [that] does not result in exposure to combustion gases.”
In short, it is at best misleading and at worst disingenuous to suggest that exposure to cannabis smoke is equal to or more harmful to health than smoking, or to suggest that there are no data to long-term on the respiratory effects of cannabis smoke. They exist and the results of these studies are clear and consistent. The risks associated with cannabis smoke and tobacco smoke are far from equal, and the public should not be chastised for rightly recognizing their differences.
By Paul Armentano, NORML : https://norml.org/blog/2023/09/05/norml-op-ed-lets-dispel-the-myth-that-cannabis-and-tobacco-smoke-are-equally-hazardous-to-health /