The Neurochemistry of Addiction

Tryptophane is the only amino acid that can be converted into serotonin. Most of the serotonin is in your gut, so why don't you expand on that process? People think if you make serotonin and take a lot of tryptophane, you're going to have it in your brain, but it doesn't. Tryptophane was one of the rarest amino acids in her diet.