Pot Doesn't Cause Lung Cancer?

Well this is counterintuitive. How is it possible that smoking marijuana does not lead to a higher chance of lung cancer. It really does not make much sense, but apparently a study funded by the National Institutes of Health's National Institute on Drug Abuse at the David Geffen School of Medicine at UCLA concludes that there was

"no association at all, and even a suggestion of some protective effect."

Dr. Tashkin also adds that

"earlier work established that marijuana does contain cancer-causing chemicals as potentially harmful as those in tobacco, he said. However, marijuana also contains the chemical THC, which he said may kill aging cells and keep them from becoming cancerous."

Pretty incredible stuff.

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