Journal of the American Medical Association put a dent in the arguments against Marijuana smoking today, with release of a new report showing casual pot smokers might even have stronger lungs than non smokers.

Researchers say that there is good evidence that occasional marijuana use can cause an increase in lung airflow rates and lung volume. Volume is measured as the total amount of air a person can blow out after taking the deepest breath they can.

The study, which was carried out by The University of California, San Francisco, and The University of Alabama at Birmingham, spans over more than two decades and involves more than 5000 men and women, in four American cities : Birmingham, Chicago, Oakland, Calif., and Minneapolis.

One of the study’s co-authors, Stefan Kertesz commented :

‘At levels of marijuana exposure commonly seen in Americans, occasional marijuana use was associated with increases in lung air flow rates and increases in lung capacity … With marijuana use increasing and large numbers of people who have been and continue to be exposed, knowing whether it causes lasting damage to lung function is important for public-health messaging and medical use of marijuana.’

He continues that even at daily usage levels of one joint […]