L-Tryptophan is a precursor to 5-HTP. L-Tryptophan is better used by the body as it is used to produce the needed neurotransmitter serotonin, melatonin and various other needed compounds. 5-HTP is only used to produce serotonin. Plus, L-Tryptophan is only converted to serotonin and others as the body needs them. 5-HTP can cause an excess level of serotonin, which can be problematic.

L-Theanine is used to produce GABA, a needed neurotrasnmitter

The third important neurotransmitter is Dopamine. Food sources of dopamine increasing tyrosine include almonds, avocados, bananas, dairy products, lima beans, pumpkin seeds, and sesame seeds. Caffeine provides a short term increase of dopamine but the effect ends quickly. Dopamine levels can be decreased by an anti-oxidant deficient diet, so vit C, vit E and the other anti-oxidants are needed.