One Joint a Week for 49 Years Doesn’t Harm Lungs, Research Finds - Bloomberg Business
Jan. 10 (Bloomberg) -- Occasional pot smoking doesn’t appear to harm users’ lungs the way regular tobacco use does, according to a 20-year study.
At the level of one marijuana cigarette a week for 49 years, or one joint a day for 7 years, there was no decline in lung function, according to a paper released today by the Journal of the American Medical Association.
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More than half of the people in the study reported current marijuana smoking, tobacco smoking, or both at one or more examinations. Tobacco smokers had eight to nine cigarettes a day at the peak of their use, versus marijuana smokers reporting about two or three episodes in 30 days.
At more than 10 years of smoking a daily joint, lung function seemed to decline although not to a degree that was statistically significant, the study found.
The studies are not supporting your claim.