["Amino acids","Sleep-support nutrients","Mood-support nutrients"]
L-tryptophan
support mood and restful sleep
Key Benefits
- Supplies an essential amino acid
- Supports serotonin and melatonin pathways
- May support selected sleep-quality measures
- Supports normal protein synthesis
How It Works
Ingredient Details
INCI Name: L-Tryptophan
Ingredient Type: ["Essential amino acid","Serotonin precursor","Dietary supplement ingredient"]
Best For
Adults seeking nutritional sleep support · People with low dietary tryptophan intake · Nighttime wellness formulas · People advised by a healthcare professional
What It Is
What It Does
L-tryptophan FAQs
Common questions about this ingredient in skincare.
What is L-Tryptophan?
It is an essential amino acid used to make proteins and as a precursor for serotonin, melatonin, niacin, and kynurenine metabolites.
Does L-Tryptophan improve sleep?
A systematic review found improvement in some sleep measures, especially wake after sleep onset, but not every sleep outcome improved.
Is it the same as 5-HTP?
No. L-tryptophan is converted to 5-HTP in one metabolic step; the two supplements have different pharmacology and evidence.
Can it support mood?
It participates in serotonin synthesis, but a supplement should not be presented as a treatment for depression or another mood disorder.
Can it interact with antidepressants?
Yes. Combining serotonergic supplements with SSRIs, SNRIs, MAO inhibitors, or other serotonin-raising drugs may be dangerous. Consult the prescriber.
Can it cause side effects?
Possible effects include nausea, dizziness, headache, or drowsiness. Avoid driving until you know your response and seek care for serious symptoms.
Shop the ingredient
Products Featuring L-tryptophan
