So glad you mentioned cannabis, Jeff. IMHO, it`s the master medicinal plant.

From the moment we are born to the moment we die we naturally make this stuff called Anadamide which binds to specific receptors on our cells as part of the Endocannbinoid System (ECS). The primary receptors are CB1/2 which among many important life preserving functions, chemically signals any cell with bad DNA to kill itself, cancer included. From a molecular standpoint, delta-9 THC is a dead ringer for Anadamide and readily binds to cells and signals in the same way. If a single reason for prohibition exists, that is probably it.

And of course THC is just one of hundreds of cannabinoids within the plant, all them medicinal, life, and health preserving.