Is Medical Marijuana harmful?

Those against Medical Marijuana use their main argument that it is harmful to users. The British lung foundation states that, “3-4 Cannabis cigarettes a day are associated with the same evidence of acute and chronic bronchitis and the same degree of damage to the bronchial mucosa as 20 or more tobacco cigarettes a day.” Hard to believe based on the fact of all of the additives that are in an actual Tobacco cigarette. Not exactly sure which this stat is based off of or whether it be based on a study or not. The British lung foundation also states that, “Cannabis smoking is likely to weaken the immune system. Infections of the lung are due to a combination of smoking-related damage to the cells lining the bronchial passage and impairment of the principal immune cells in the small air sacs caused by cannabis." This seems to be a little bit of a farfetched statement. Not very creditable when they use the words likely in their arguments. On the contrary, Professor Lester Grinspoon of Harvard Medical School states, “Although cannabis has been smoked widely in Western countries for more than four decades, there have been no reported cases of lung cancer or emphysema attributed to marijuana.” You would think if 3-4 Cannabis cigarettes are equal to 20 or more tobacco cigarettes that there would be evidence of lung cancer or emphysema associated with them. The real question is what side do you believe?

Grinspoon, Lester. "Puffing Is the Best Medicine." Los Angeles Times. (2006): n. page. Web. 25 Jun. 2013.

, ed. "Smoking Gun: The Impact of Cannabis Smoking on Respiratory Health." http://www.lunguk.org/. British Lung Foundation. Web. 25 Jun 2013. <http://medicalmarijuana.procon.org/view.source.php?sourceID=798>.