What is tryptophan?

Tryptophan is an amino acid that plays a pivotal role in the synthesis of serotonin, which is important for maintaining a healthy mood. In one part of the Huberman Lab, Andrew Huberman explains that tryptophan can be found in various foods and acts as the amino acid precursor upstream of serotonin synthesis. The example often cited is the "tryptophan effect" from eating white meat turkey, which is said to cause sleepiness due to its high tryptophan content. However, Dr. Huberman clarifies that sleepiness is often due to overeating rather than tryptophan alone. Foods such as milk, oats, cheese, chocolate, and certain fruits like bananas and apples also contain tryptophan 1.

Additionally, Andrew Huberman discusses that under conditions of inflammation, tryptophan may be diverted away from serotonin production into a neurotoxic pathway, which can exacerbate depressive symptoms. Tryptophan enters the body via diet, and its diversion in the case of inflammation highlights the complex interaction between diet, mood, and brain chemistry 2.