Short answer : in absolute terms, smoking weed creates more tar and other nasty compounds than tobacco.
However, you normally smoke a **lot** less weed than your do tobacco.
Second, substances in smoked cannabis also trigger/enhance apoptosis. That’s the process that causes cells with mutations or other damage to stop reproducing and die. We *think* that there are better outcomes with pot, and fewer instances of problems because apoptosis triggers cause damaged cells to die rather than hanging around and reproducing, and accumulating more damage until they hit a malignant mutation.
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