There are molecules in brain whose shape is matched to bond with cannabis.
Here is 20 benifits of weed.
Those opposed to weed basically are old school infantiles that are paranoid of anything outside of anything that is outside their personal purview.
We now know that some magic mushrooms induce the growth of new brain cells { nerves } and there is also a long list of pros associated with magic shrooms and their active ingredients when used appropriately.
Used knowledgeably is what apply's to any substance. The infantile adult brain is paranoid of truth when it appears to be detrimental to their ego and traditional ways of they are above the others and don't approach them with anything that takes them off their spiritually-dry, high horse.