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L-Tryptophan 500 mg

product on market Tablet or Pill Source Naturals Safety: 100/100
100/100

This product looks safe

  • No ingredients exceed tolerable upper intake levels
  • 25% of ingredients have research evidence
B Label Compliance Grade

What the Evidence Says

AI-generated · Qwen 3.6 · methodology

L-tryptophan is a precursor to serotonin, with moderate evidence supporting its role in sleep and mood regulation. Vitamin B6 and calcium act as cofactors in the synthesis of neurotransmitters. Research coverage for this specific combination is limited, though the individual components are well-studied for metabolic support.

AI-generated summary based on research evidence. Not medical advice.

Label

Product Label

Label for L-Tryptophan 500 mg
Open Full PDF View on NIH DSLD →
Details

Label Data

1 Tablet(s)
Serving Size
20
Servings
Other Combinations
Product Type
25%
Evidence Coverage
Ingredients

Supplement Facts — Evidence Check

9 mg (529% DV)
6.9× RDA — above typical dose (UL: 100 mg) 114 studies (A:3, B:35)
Calcium
57 mg (4% DV)
Iron
0.6 mg (3% DV)
1.5 Gram(s)
Market median: 500.0mg (70 products)

Other Ingredients

Dibasic Calcium Phosphate Stearic Acid modified Cellulose Gum Magnesium Stearate Silica
Claims

Label Claims — Verification

Unverified Nutrient
Unverified All Other
Unverified Structure/Function
Info

Product Information

Directions for Use

Suggested Use: 1 tablet three times daily, between meals and preferably with fruit juice. To support restful sleep, take an additional 3 tablets before bed.

Warnings & Precautions

Caution: If you are pregnant, may become pregnant, breastfeeding, or are taking medications such as SSRIs or MAOIs consult your health care professional before using this product.

Do not use if either tamper-evident seal is broken or missing.

Keep out of the reach of children.

Warning: Accidental overdose of iron-containing products is a leading cause of fatal poisoning in children under 6. Keep this product out of reach of children. In case of accidental overdose, call a doctor or poison control center immediately.

Formulation Notes

L-Tryptophan with coenzyme B-6

Mood enhancement and sleep

The essential amino acid L-tryptophan helps support relaxation, restful sleep, and a positive outlook. It plays a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response. This tryptophan includes the activated coenzyme form of vitamin B-6, called P-5-P, that is required to convert tryptophan to serotonin. L-Tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-tryptophan converts to niacin in the body, which supports circulation, a healthy nervous system, the metabolism of food, and the production of hydrochloric acid for the digestive system. Source Naturals L-Tryptophan is extremely pure and is regularly tested to ensure the highest standards of quality.

Additional Information

Store in a cool, dry place.

Metadata

Product Details

UPC / SKU0 21078 01987 9
DSLD Entry Date2022-11-22
Product TypeOther Combinations
FormTablet or Pill
DSLD ID274809
Data Updated2026-04-11
Research

Research Evidence

29
Research Sources
48
Avg Quality
19
Rct
5
Meta Analysis
3
Systematic Review
2
Clinical Trial
B Prebiotic and probiotic supplementation and the tryptophan-kynurenine pathway: A systematic review and meta analysis
Meta Analysis Neuroscience and biobehavioral reviews 2021 PubMed DOI
B Tryptophan and 5-hydroxytryptophan for depression
Systematic Review The Cochrane database of systematic reviews 2001 PubMed
B Tryptophan and 5-hydroxytryptophan for depression
Systematic Review The Cochrane database of systematic reviews 2002 PubMed
B The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression
Meta Analysis Nutrition reviews 2022 PubMed DOI
B No effects of acute tryptophan depletion on anxiety or mood in weight-recovered female patients with anorexia nervosa
Rct European archives of psychiatry and clinical neuroscience 2023 PubMed DOI
C The association between tryptophan levels and postpartum mood disorders: a systematic review and meta-analysis
Meta Analysis BMC psychiatry 2022 PubMed DOI
C A systematic review of the effect of L-tryptophan supplementation on mood and emotional functioning
Systematic Review Journal of dietary supplements 2021 PubMed DOI
C Comparison between Acupuncture and Nutraceutical Treatment with Migratens® in Patients with Fibromyalgia Syndrome: A Prospective Randomized Clinical Trial.
Rct Nutrients PubMed DOI
C Intake of Lactiplantibacillus plantarum HEAL9 Improves Cognition in Moderately Stressed Subjects: A Randomized Controlled Study.
Rct Nutrients PubMed DOI
C Are tryptophan and 5-hydroxytryptophan effective treatments for depression? A meta-analysis
Meta Analysis The Australian and New Zealand journal of psychiatry 2002 PubMed
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This product page is for informational purposes only and does not constitute medical advice. Always consult your healthcare provider before taking any supplement.