Marijuana was given a bad rep years ago for what seems to be all the wrong reasons; however we’ve come a long way since the days of reefer madness.
It’s understandable to believe anything you smoke contributes to lung cancer or pulmonary impact of some kind but science tells a different story.
In 2006, a study was completed by pulmonologist, Dr. Donald Tashkin which was the biggest case-control study ever completed, totalling about 2,200 subjects. To his amazement, he found no link to cancer and no real pulmonary impact at all but he did find a clear increase in cancer was seen among cigarette smokers in the study. This study includes cannabis smokers who have smoked well over 22,000 joints! They were found to have no greater risk than a non-user.
Actually, THC, “the active ingredient in marijuana cuts tumor growth in common lung cancer in half and significantly reduces the ability of the cancer to spread, say researchers at Harvard University who tested the chemical in both lab and mouse studies.”, according to Science Daily who reviewed a study by The American Association for Cancer Research.
Additionally, in 2012, The Journal of the American Medical Association (JAMA) reported on a 20 year study that concluded “Occasional and low cumulative marijuana use was not associated with adverse effects on pulmonary function.”
In the world of science, this has been replicated numerous times.
With that said, the smoke from burning marijuana leaves does actually contains several known carcinogens and the tar it creates contains 50 percent more of some of the chemicals linked to lung cancer than tobacco smoke. A joint also deposits four times as much of that tar as an equivalent tobacco one. So you may jump to conclusions and think – wow this is so bad for you and must cause cancer worse than tobacco – however, as mentioned, scientists found no increased risk for lung cancer or pulmonary impact. This is said to be due to the unique properties of the cannabis plant itself.
Lastly, according to Dr. Tashkin’s latest review in Annals of the American Thoracic- “He found that the evidence does not indicate that habitual use of marijuana leads to significant abnormalities in lung function when assessed either cross-sectionally or longitudinally, except for possible increases in lung volumes and modest increases in airway resistance of unclear clinical significance.”