Paul Saladino· MD
for a long time and in fact I've had this argument with many doctors and they were crushing me down by saying like there is no evidence that serotonin produced in the gut affects the brain well now there is now there is first of all it affects the brain through the vagus nerve right second of all second of all now we have evidence that serotonin actually preforms serotonin which was claimed medicinal skin for a long time that it cannot cross the broad brain barrier it does cross it just like they claim for Gaba could not Crest cross the blood-brain barriers so they could gather supplements apparent it was useless yes it does so now even though you're producing 90 of the serotonin in your GI tract a lot of it if it starts circulating into your bloodstream will actually go to the brain and directly start affecting the brain