The Way to Better Mental Health May Go Through Your Stomach
https://bcmp.hms.harvard.edu/news/getting-how-gut-bacterias-connection-depression
https://magazine.publichealth.jhu.edu/2021/gut-microbiome-and-brain
The Way to Better Mental Health May Go Through Your Stomach
https://bcmp.hms.harvard.edu/news/getting-how-gut-bacterias-connection-depression
https://magazine.publichealth.jhu.edu/2021/gut-microbiome-and-brain
How do drugs work then? Many are structurally similar to serotonin and are pretty effective when ingested (psilocybin, LSD, …).
They, or products of these drugs, do cross the BBB, and stimulate the same (sub)receptors as serotonin or dopamine.
Endorphin doesn’t cross the barrier but morphine does, we basically find ways to sneak stuff into the brain.