Tryptophan

Tryptophan is an essential amino acid used to make proteins. The body does not make it, so it must be consumed in the diet. After we eat tryptophan, the body converts some to 5-HTP and then into the neurotransmitter serotonin. The body also converts some tryptophan to nicotinamide adenine dinucleotide (NAD), which is why tryptophan is also considered a dietary source of niacin. 

​

There are two types of tryptophan: L-tryptophan and D-tryptophan. The only difference between the two types is the orientation of the molecule. You can get tryptophan through certain foods or a colostrum supplements