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Disturbing, although inconclusive, news for the cannabis community just rose from the belly of mainstream media: Cannabis may leave consumers more susceptible to paraseptal emphysema than cigarettes, a new study conducted by Canadian researchers suggests. The investigation, whose results were published on Tuesday in Radiology, found that twice as many weed smokers developed the condition compared to individuals who consume cigarettes alone. 

“93% of the marijuana smokers had emphysema rather than 67% of the tobacco-only smokers,” the study’s lead author Giselle Revah told Medical News Today.

A note before we proceed: Due to prohibition-era legal restrictions and societal stigma, the study of cannabis has not been able to progress to the point where we have definitive answers regarding its effects on our bodies. Remember, one scientific study does not indicate conclusive findings. Certainly, when it comes to cataclysmic tidings of what weed can do to the human form, you damn well should be cynical, given the generations of Reefer Madness that we’ve been forced to ingest. But hey, we’re all about giving you the information at hand here at MERRY JANE.

The study, which was published in a journal associated with the Radiological Society of North America, looked at chest scans of weed smokers versus people who only smoke tobacco. The image analyses showed that airway changes — inflammation and paraseptal emphysema — are more often experienced by people who smoke weed than non-smokers and cigarette smokers.

The study’s authors posited that the danger of cannabis could be due to the way tokers hold smoke in their lungs longer (please be advised this practice doesn’t make you any more stoned!) or are more likely to eschew filters than cigarette smokers.

Paraseptal emphysema, mind you, is not as lethal as other forms of the disease that are more closely correlated to cigarette smoking. It impacts the lungs’ small air sacs, which play a pivotal role in swapping carbon dioxide out for oxygen. Nonetheless, it can lead to shortness of breath, a chronic cough, fatigue, persistent mucus in the throat, and in some cases, a collapsed lung, which can prove to be fatal.

“Emphysema is a disease of the small air sacs in the lungs when the walls of those sacs get damaged,” said Revah, a cardiothoracic radiologist at Ottawa Hospital and an assistant professor at the University of Ottawa. “Small holes are created in the lung, and in those areas, the gas exchange function of the lung is impaired (taking in oxygen and removing carbon dioxide).”

The investigation examined 146 participants, including 56 cannabis consumers, 57 non-smokers, and 33 tobacco consumers.

Medical News Today also contacted a pulmonologist who added a note of caution to this study’s cannabis-specific findings, implying that weed or tobacco additives also greatly impact lung health.

“Any inhalation of particulate matter, whether tobacco smoke or marijuana, causes inflammation within the airways,” said S. Thomas Yadegar. “However, both additives, including flavors, preservatives, and pesticides, can be highly variable between cannabis and tobacco products.”

But again, it’s important to read the full breadth of available scientific findings — particularly before jumping to conclusions about limiting access to cannabis. While it could impact overall lung health, cannabis is also a harm-reduction tool. For example, an October study from Johns Hopkins, New York University, and the American Heart Association found that legal access to weed protected consumers from vaping-related lung injuries.