What is more harmful – marijuana or a cigarette?
Marijuana is less harmful because it is usually smoked much less, even by heavy smokers. Besides, its smoke contains less harmful chemicals. It has not been possible to establish a link between smoking cannabis and the occurrence of lung cancer.
Also there is relatively little tobacco in modern cigarettes, but a lot of different impurities reducing the cost of production. Thus, if you smoke the same amount of tobacco mixture from a cigarette and marijuana, then the harm from the combustion products of the tobacco mixture will be an order of magnitude higher. If we compare cigars that are produced only from selected tobacco, and marijuana, then again, the harm to the body from the cigar will be an order of magnitude more due to the combined effects of combustion products and nicotine on the body.