Tobacco smoke and marijuana smoke have some things in common. For example, they are both "smoke." Yet it appears there are some significant differences between the two, according to a study conducted by University of California San Francisco researchers.
For starters, one causes lung problems and the other doesn't.
Researchers found no link between marijuana smoke and emphysema, or any of the other pulmonary problems associated with cigarettes. In fact, some light marijuana users had higher lung function that nonsmokers.
The findings are the fruits of a 20-year study in which over 5,000 marijuana
users in four cities were examined between 1985 and 2006. The study's
authors stop short of recommending that pot be issued to all citizens,
but they do corroborate some previous findings.
The study was published today in the Journal of the American Medical Association (subscription required to read the study in full), and has received nonstop international media attention.
Perhaps troubling for frequent tokers, the "typical" light use in the study is two to three joints or pipe bowls over a 30-day period. For others, it could be one set at a Phish concert.
The study corroborates other similar findings: Donald Tashkin, who runs the pulmonary center at UCLA's David Geffen School of Medicine, found no link between marijuana use and lung problems, even in users who had smoked the equivalent of a joint a day for 50 years.
At the least, this study shouldn't be interpreted as an endorsement of marijuana use -- merely a lack of evidence that it makes lung function worse, according to health experts interviewed by WebMD.
"Marijuana does irritate airways, and certainly anyone who's heard someone cough after smoking marijuana knows that," one said. "Is this actually a real benefit to lung health? Probably not."
So don't throw away your vaporizer, and no need to give up on the brownies!
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