A new government study has found that regular marijuana usage may not cause long-term lung damage.
The study, backed by the National Institute of Health, consisted of 5,100 men and women from Oakland, Calif., Chicago, Minneapolis and Birmingham, Ala. In the 20-year study, more than half of the participants, who began the study at the average age of 25, smoked cigarettes, marijuana or both.
Participants took a deep breath into a respirator and researchers measured the amount of air they could force out within one second. The test measured marijuana’s effects on pulmonary function and whether marijuana usage caused damage such as chronic obstructive pulmonary disease.
According to the results, marijuana users performed better than cigarette smokers, and slightly better than non-smokers, a result of marijuana smokers’ experience with practiced inhalation.
Furthermore, results showed that a person can experience seven “joint years”, which is equal to 365 days of smoking one joint or filled pipe a day, without worsening pulmonary function. The study also showed that it would take 10 joint years before lung function declined.
Marijuana usage still demonstrated the short-term effects of coughing, irritated airways, reduced attention, lowered attention and higher risk for accidents.
While other studies have come to similar conclusions, this study is the most extensive of its kind, consisting of thousands of subjects and spanning a longer amount of time, according to a report in The New York Times.
Linda Spear, a Binghamton University professor specializing in behavioral neuroscience, said she found the study to be shocking, but not implausible.
“At first I was surprised at the lack of lung effects of smoking marijuana, relative to the clear effects seen when smoking cigarettes,” Spear said. “After thinking about it, though, it may just be a differential exposure effect — cigarette smokers typically smoke more cigarettes and hence inhale more smoke than the typical marijuana user.”
However, Spear said she does not believe the study justifies the legalization of marijuana.
“One study showing a lack of lung damage is encouraging, but does nothing to mitigate the many studies showing that development of cannabinoid systems and other neural systems in the brain, as well as vulnerability for the development of psychopathology, is altered by cannabinoid exposure during adolescence/emerging adulthood,” Spear said.
Gary Truce, a professor of health and wellness at BU, said he thinks the study does not portray the true nature of marijuana users.
“This study states that it takes 10 years for marijuana to harm the lungs, but assumes smokers will limit themselves to one marijuana cigarette a day,” Truce said. “Marijuana is like candy or gambling — once you start, it’s hard to stop. A person can’t limit it unless they have impossible self-discipline.”
Rownok Nowrose, a sophomore in the School of Management, expressed mixed feelings about marijuana use.
“I believe marijuana can sometimes be useful, for instance with medicinal use, religious use, and not to mention it is not as bad as alcohol, which is legal,” Nowrose said. “However, there are some bad things. It’s addictive, it causes you to do nothing and you can end up a failure.”
Nowrose added that the study supports the legalization of marijuana.
Evan Shamon, a sophomore majoring in computer science, said he supported the legalization of marijuana prior to learning about the study.
“[Marijuana] should be legalized considering just how prolific it is in society,” Shamon said. “It’s safe. It’s fun. If it’s your thing of choice, go for it.”