NEW ZEALAND – While their British counterparts unearthed a link between marijuana and psychotic disorders, researchers in New Zealand discovered that smoking a single joint of marijuana can do just as much damage as five cigarettes.
Staff at New Zealand’s Medical Research Center divided the study’s 339 subjects into four groups based on smoking habits: tobacco-only smokers, cannabis-only smokers, those who smoked tobacco and cannabis, and non-smokers. Over the course of three years, they found that cannabis users suffered lung damage in both the large and small airways. According to the paper released July 31 in the Thorax journal, it took between 2.5 and 5 tobacco cigarettes to cause as much harm as one joint of marijuana.
Signs of emphysema, however, dropped for cannabis users. Almost 19 percent of the tobacco-only smokers showed symptoms, while their pot-exclusive counterparts got away with a mere 1.3 percent.
In Great Britain, a group of researchers led by Dr. Glyn Lewis of the University of Bristol studied how THC, the key active chemical in marijuana, affects the brain. The study, which appeared in The Lancet on July 27, found that cannabis use had a strong connection to personality changes, hallucinations and other psychotic disorders. It may even be responsible for more than 10 percent of schizophrenia incidents.
Meanwhile, as marijuana use spreads from college-age users to high school students, the dangers are escalating. Pot for sale on the street today contains three times as much THC as pot available 30 years ago, according to the U.S. National Institute on Drug Abuse.