L-Tryptophan 500 mg®
Amino Acids & ProteinBrand: Source Naturals
Functions
Net Contents
100 Gram(s)
Serving Size
0.5 Gram(s)
Servings Per Container
66
Supplement Form
Liquid
Bar Code (UPC/SKU)
0 21078 01999 2
Product Version
SN1999 REV K071
Label Analysis
Objective insights generated automatically from the official DSLD label — a quick, factual read of how this product is formulated and disclosed.
Single-ingredient formula listed in Supplement Facts.
Every active ingredient discloses a specific amount per serving.
Label states: Vegetarian, Gluten-Free.
This analysis is generated algorithmically from label data for educational reference only. It is not a product endorsement, ranking, or medical advice.
Allergen Guide
Contains
- Milk
- Egg
- Wheat
- Soy
- Gluten
Allergen flags are parsed automatically from the official label's claims and statements. Always verify against the physical product label before use, especially if you have a severe allergy.
Supplement Facts
Serving Size: 0.5 Gram(s) · 3 per day
| Ingredient | Amount Per Serving | |
|---|---|---|
| L-Tryptophan | 1.5 Gram(s) | — |
Not Present
Target Groups
Label Claims
Directions & Suggested Use
Suggested/Recommended/Usage/Directions
Suggested use: 1/4 teaspoon three times daily, between meals and preferably with fruit juice. To support restful sleep, take 3/4 teaspoon before bed.
Warnings & Precautions
Precautions re: Pregnant or Nursing or Prescription Medications
Caution: If you are pregnant, may become pregnant, breastfeeding, or are taking medications such as SSRI's or MAOI's consult your healthcare professional before using this product.
Precautions re: All Other
Do not use if tamper-evident seal is broken or missing.
Precautions re: Children
Keep out of the reach of children.
Formulation
Formula re: Contains
The essential amino acid L-tryptophan helps support relaxation, restful sleep, and feeling better. It plays, a part in the synthesis of both melatonin and serotonin, hormones involved with mood and stress response. L-tryptophan also supports immune functions because it is the body's precursor to the kynurenines that regulate immunity. If needed, L-tryptophan concerts 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.
Formulation re: Vegetarian/Vegan
Suitable for vegetarians and hypoallergenic: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.
Formulation re: Other
Suitable for vegetarians and hypoallergenic: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.
Formulation re: Does NOT Contain
Suitable for vegetarians and hypoallergenic: contains no yeast, dairy, egg, gluten, corn, soy or wheat. Contains no sugar, starch, salt, preservatives, or artificial color, flavor or fragrance.
FDA Statements
FDA Disclaimer Statement
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
FDA Statement of Identity
Dietary Supplement
Other Label Statements
Brand IP Statement(s) re: (c), (TM), (SM)
Copyright Source Naturals, INC.
Manufacturer & Distributor
Manufacturer
Source Naturals, Inc.
P. O. Box 2118, Santa Cruz, CA, 95062
Market Reference
Source Naturals L Tryptophan
Vitacost.com4.6(1100)$12.42Source Naturals L-Tryptophan with Coenzyme B-6
Vitacost.com4.6(297)$21.97Source Naturals L-Tryptophan 500mg 30 Cap
Four Seasons Natural Foods4.6(1100)$9.59Source Naturals Serene Science L- Tryptophan 500mg 60 Capsule
Herbs Direct$13.73Best Naturals L- Tryptophan 500 Mg 120 Capsules
Target$26.95NOW Foods L- Tryptophan Relaxation Support Capsules
Vitacost.com4.6(4100)$13.46Nutricost L- Tryptophan Capsules
Target4.1(231)$15.95The Vegan Shoppe L- Tryptophan 500mg 120 Veggie Capsules
The Vitamin Shoppe4.7(45)$36.99
Where to Buy Locally
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Willner Chemists
4.7 (146)Vitamin & supplements store
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Research & Studies
Tryptophan As A Nutraceutical–Clinical And A Critical
MR Suchitra, P Krubaa, S Parthasarathy - European Journal of Molecular & … - academia.edu
… L Tryptophan is available in the commercial product as 125 mg/ capsule or 500 mg/ capsule … was lowered in preeclamptic compared with the healthy placental arteries, consistent with …
Tryptophan As A Nutraceutical–Clinical And A Critical
MR Suchitra, P Krubaa, S Parthasarathy - European Journal of … - painfreepartha.com
… L Tryptophan is available in the commercial product as 125 mg/ capsule or 500 mg/ capsule … was lowered in preeclamptic compared with the healthy placental arteries, consistent with …
l-Tryptophan
BMD Knapp, MJ Cupp, TS Tracy - … Supplements: Toxicology and Clinical …, 2003 - Springer
… ill patients who might be of generally worse health than controls and therefore more likely to use a dietary supplement such as L-tryptophan. Of the patients identified with eosinophil …
20035 citationsAnalysis, nutrition, and health benefits of tryptophan
M Friedman - International Journal of Tryptophan Research, 2018 - journals.sagepub.com
… Here, tryptophan refers to l-tryptophan and the isomeric form produced during food … in the absence of l-tryptophan; ie, the mice must meet the entire need for l-tryptophan from the d-…
2018402 citationsTryptophan and its role in sleep and mood
P Yousef, J Rosen, C Shapiro - Studies in Natural Products Chemistry, 2024 - Elsevier
… It is consumed from different food sources in the form of L-tryptophan. In this chapter, we review the … In the pediatric population, l-tryptophan can be safely and effectively used to manage …
202420 citationsEffectiveness of Silymarin, Sulforaphane, Lycopene, Green Tea, Tryptophan, Glutathione, and Escin on Human Health: A Narrative Review.
F Sebastiani, C D'Alterio, C Vocca, L Gallelli… - Uro, 2023 - search.ebscohost.com
… There is an enormous amount of substances and actives of natural origin that are known for their purported health benefits. The aim of this review is to narratively summarize the …
202310 citations
Data sourced from the U.S. National Institutes of Health, Office of Dietary Supplements Dietary Supplement Label Database (DSLD) · Label entered 2023-09-25. DSLD Label ID: 295957. This information is provided for educational reference only and is not medical advice. Always follow the product label and consult a doctor or pharmacist before use.
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