Tryptophan is an essential amino acid that supports brain chemistry, energy production, and the production of mood-regulating neurotransmitters.[1][2][3] It helps with sleep through conversions to serotonin and melatonin.[1][3][4] In brain aging or neurological diseases, this system is disrupted and tryptophan is diverted to harmful byproducts.[5][7] These products have been linked to memory loss, mood swings, and sleep problems.[1][4][7] Low levels of tryptophan impair long-term memory and cognition without the need for depression.[1][4] In Alzheimer's disease, the degradation of tryptophan is increased, which reduces serotonin in the brain.[7] Stabilization of tryptophan levels protects against anxiety in panic disorders.[1]