I have to wonder what the prevalence of psychedelics and antidepressants has done at a population level to change us.

A Multidisciplinary Hypothesis about Serotonergic Psychedelics. Is it Possible that a Portion of Brain Serotonin Comes From the Gut? https://pubmed.ncbi.nlm.nih.gov/36137971/

Seeking the Psilocybiome: Psychedelics meet the microbiota-gut-brain axis https://www.sciencedirect.com/science/article/pii/S169726002...

Serotonin Reuptake Inhibitors and the Gut Microbiome: Significance of the Gut Microbiome in Relation to Mechanism of Action, Treatment Response, Side Effects, and Tachyphylaxis https://www.frontiersin.org/articles/10.3389/fpsyt.2021.6828...