Andrew Huberman· PhD
That said, I know a number of people use 5-HTP supplementation outside of sleep, or I should say during the daytime to try and increase serotonin and it will indeed increase circulating serotonin. But again, people vary in their sensitivity to these sorts of things. Some people might find for instance, that 300 milligrams of 5-HTP is just far too much. It blunts their appetite, might even reduce libido.