With a growing number of Western countries decriminalizing or outright legalizing cannabis, the controversial plant seems set to become an acceptable alternative to some preexisting treatments for appetite loss, chronic pain and more. Yet some supporters of medicinal marijuana products argue the chemicals in this plant can do much more than just make someone hungry or ease their pain -- marijuana, they argue, may actually cure cancer, and this is something the established pharmaceutical industry doesn't want you to know. So how do these claims hold up?