Everyone knows about THC, and everyone is getting to know CBD. These are cannabinoids—phytochemicals within the Cannabis sativa plant with bioactive benefits. Specifically, cannabinoids are 21-carbon molecules that influence the body’s endocannabinoid receptors. Everything from brain function to the immune system to mental health is influenced by the endocannabinoid system. This system was teased out only in 1988, by Israeli researcher Raphael Mechoulam. But guess what? There are actually 150 cannabinoids all told that are unique within cannabis. Whoa. There’s much we still don’t know about Nature’s Most Nearly Perfect Plant.

On CBD itself, here’s what we DO know. There are at least a dozen different health conditions under research with cannabidiol. Of note is that dietary supplements play under a different set of rules than do drugs, so they cannot claim to diagnose, treat, cure or prevent any disease. That means that some of the health conditions below—epilepsy, Parkinson’s, multiple sclerosis, autism, glioblastoma—cannot be talked about in a health food store setting because these are diseases, which are out of bounds for dietary supplements.

Also of note, research studies do a poor job in characterizing the material under review, so in most cases we do not know whether this is hemp-derived CBD or marijuana-derived CBD, as is the case with the pharmaceutical drugs, Epidiolex and Sativex, under investigation and review by the FDA.