Pubdate: Thu, 12 Jan 2012 Source: Nanaimo Daily News (CN BC) Copyright: 2012 Nanaimo Daily News Contact: http://www.canada.com/nanaimodailynews/ Details: http://www.mapinc.org/media/1608 Author: Derek Abma, Postmedia News LIGHT POT SMOKING DOSEN'T CAUSE LUNG DAMAGE Light to moderate marijuana smokers show no signs of lung damage, in contrast to cigarette smokers, according to results of a study conducted in the United States. A report to be published Wednesday in the Journal of the American Medical Association shows that, over a 20-year period, pot smokers generally did not experience a loss in lung functioning. Many actually had enhanced lung capacity, which one researcher involved in the study speculated might come from the common practice of holding one's breath after inhaling cannabis smoke to maximize its intoxicating effects. On the other hand, cigarette smokers were found to have less capacity in the amount of air they could exhale, and also in the speed at which they could empty the air from their lungs. The study included more than 5,000 people in the U.S., who were assessed between 1986 and 2006. "Marijuana may have beneficial effects on pain control, appetite, mood and management of other chronic symptoms," researchers from the University of California, University of Alabama and Northwestern University said in a statement. "Our findings suggest that occasional use of marijuana for these or other purposes may not be associated with adverse consequences on pulmonary function." There was a decline in lung function found among pot smokers who were using the drug as frequently as 20 times a month, but the median usage rate among the marijuana smokers in this study was two to three times a month. Tobacco smokers in this study at the mid-range smoked eight to nine cigarettes a day. Stefan Kertesz, a professor of medicine at the University of Alabama who contributed to the study, said the low amount of marijuana generally smoked by subjects in comparison to the tobacco quantities is likely "crucial" to the findings. He said it remains inconclusive whether the substances themselves differ in how harmful they are to people's lungs. "Tobacco smokers in this study are smoking what is really orders of magnitude more tobacco than marijuana smokers are smoking marijuana," he said. Kertesz said the study did not address possible links between marijuana and fatal diseases such as lung cancer and cardiovascular disease, which have been found to result from tobacco smoking. However, he said past research has not shown connections between marijuana and these diseases. - --- MAP posted-by: Jo-D