L-Tryptophan
amino acid
ApprovedGeneral information about nutrients. No diagnosis, no medical advice. If you take medication, are pregnant or have a medical condition, talk to your doctor before taking supplements.
Overview
Essential amino acid and precursor to serotonin and melatonin.
Interactions
Iron is a cofactor for tryptophan hydroxylase (TPH), the rate-limiting enzyme that converts tryptophan to 5-HTP. Iron deficiency directly impairs serotonin synthesis.
B6 (PLP) is the essential cofactor for aromatic amino acid decarboxylase, which converts 5-HTP to serotonin.
Top 5 food sources
Expert opinions
Dr. Strunz
Strunz describes tryptophan as the rate-limiting precursor of serotonin and, downstream, melatonin. He recommends 500 to 1,500 mg on an empty stomach in the evening, taken with vitamin B6 (as P-5-P) and magnesium, the cofactors for 5-HTP conversion. Daytime protein meals compete with tryptophan for the LAT1 transporter into the brain, which is why he prefers evening intake with carbohydrate. Contraindicated with SSRIs due to serotonin syndrome risk, and caution is needed in bipolar disorder.
Recommended dose: 500–1500 mg
Source: Dr. Strunz
Expert profiles summarise publicly available statements. The named people do not cooperate with Stackwell and have not authorised these summaries. Not medical advice.
Avoid combining with SSRIs due to serotonin syndrome risk.