“Marijuana does not impair lung function—at least not in the doses inhaled by the majority of users, according to the largest and longest study ever to consider the issue, which was published today in the Journal of the American Medical Association.

Researchers working on a long-term study of risk factors for cardiovascular disease (the Coronary Artery Risk Development in Young Adults or CARDIA study) tested the lung function of 5115 young adults over the course of 20 years, starting in 1985 when they were aged 18 to 30.

The study was “well conducted” and is “essentially confirmatory of the findings from several previous studies that have examined the association between marijuana smoking and lung function,” says Dr. Donald Tashkin, professor of medicine at UCLA and a leading scientist in the area. He was not associated with the new research.

“The major strengths of this study are that it included a far larger number of subjects followed for longer than any of these previous studies,” he adds.”

Read more: http://healthland.time.com/2012/01/10/study-smoking-marijuana-not-linked-with-lung-damage/