JL-- this floored me, I didnt know either, and I am always looking for seratonin boosters.

Dopamine and serotonin seem to be opposers. Getting the serotonin right, then balancing the right level with dopamine has been H_E_L_L. If I get too much dopamine late in the day I cannot fall asleep, no matter the amount of serotonin ( which makes melanin). THen a couple days ago, I suspect I had too much serotonin, and fell asleep for a long afternoon nap.