What foods contain tryptophan?

A lot. Many foods contain tryptophan, an essential Amino Acid that you can only get through diet. Chicken and turkey both have tryptophan. It is required for the production of melatonin, a critical compound for our circadian sleep rhythms. Many people believe that tryptophan induces sleep, while usually it is the large fatty meals that make us feel tired and not the ingestion of tryptophan alone.