I think this is a really interesting question, as new directions in research and understanding are showing us that there are endogenous levels of psychoactive chemicals flowing all the time (specifically DMT and endocannabinoids).
So if someone has a higher baseline level of DMT and endocannabinoids they're going to be less-depressed and healthier, but they're also going to have a different reality than you do, cause they're a little "fucked up" all the time (but not really, cause it is their absolute normal--any less would be deficient).
Chances are many of us have depressed endocannabinoid systems, which not only leads to higher use of cannabis but a host of other problems--basically relating to every auto-immune disorder in existence, plus touching on most conditions out there, at least peripherally. New research basically supports the hypothesis that cannabinoids are incredible immuno-modulators, and without the proper level, you will get sick (precisely what you get sick with is the roll of the dice--could be Crohn's, could be fibromyalgia, could be cancer).