L-Tryptophan 500 mg®
Amino Acids & ProteinBrand: Protocol For Life Balance
Functions
Net Contents
60 Veg Capsule(s)
Serving Size
1–2 Veg Capsule(s)
Servings Per Container
30
Supplement Form
Capsule
Bar Code (UPC/SKU)
7 07359 10166 1
Product Version
CODE P0166 V6
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: Vegan, Vegetarian, Non-GMO, Gluten-Free.
This analysis is generated algorithmically from label data for educational reference only. It is not a product endorsement, ranking, or medical advice.
Supplement Facts
Serving Size: 1–2 Veg Capsule(s) · 2 per day
| Ingredient | Amount Per Serving | |
|---|---|---|
| L-Tryptophan | 1 Gram(s) | — |
Not Present
Other Ingredients
Target Groups
Label Claims
Directions & Suggested Use
Suggested/Recommended/Usage/Directions
Suggested Usage: Take 1-2 capsules twice daily on an empty stomach, with final dose at bedtime, or as directed by your healthcare practitioner.
Warnings & Precautions
Precautions re: Pregnant or Nursing or Prescription Medications
Cautions/Interactions: Tryptophan supplements may interact with CNS depressants, antidepressants (SSRIs, MAOIs), and other serotonergic agents such as St. John's Wort and 5- HTP. Consult your healthcare practitioner if you are taking medications or herbs, are pregnant/nursing, or if you have liver impairment.
Precautions re: All Other
May cause drowsiness. Do not use with alcoholic beverages or while operating heavy machinery.
Precautions re: All Other
Do not eat freshness packet. Keep in bottle.
Precautions re: Allergies
Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients. Produced in a GMP facility that processes other ingredients containing these allergens.
Formulation
Formulation re: Vegetarian/Vegan
Vegetarian/Vegan
Formulation re: Does NOT Contain
Not manufactured with wheat, gluten, soy, milk, egg, fish, shellfish or tree nut ingredients.
Formulation re: Does NOT Contain
Non-GMO
FDA Statements
FDA Statement of Identity
A Dietary Supplement
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.
Other Label Statements
General: Product/Version Code
CODE P0166 V6
General Statements: All Other Content
~ Encourages positive mood* ~ Supports relaxation & restful sleep*
Seals/Symbols
Non-GMO
General Statements: All Other Content
How It Works: L-Tryptophan is an essential amino acid; therefore, it is not synthesized by the body and must be obtained from the diet. In the brain, Tryptophan is converted into serotonin, a neurotransmitter involved in feelings of well-being, calmness, personal security, and relaxation.* It also plays a role in the regulation of appetite and synchronization of sleep patterns.*
Brand IP Statement(s) re: (c), (TM), (SM)
Every lot of Protocol For Life Balance L-Tryptophan is tested to be free of Peak E and microbial contamination.
General Statements: All Other Content
Natural color variation may occur in this product.
Manufacturer & Distributor
Manufacturer
Protocol For Life Balance
395 S. Glen Ellyn Rd., Bloomingdale, IL, 60108, USA
Market Reference
Protocol For Life Balance L-Tryptophan 500 mg
Vitacost.com4.7(143)$23.00L-Tryptophan 500 mg. (60 vegetarian capsules) ~ Protocol for Life
vitalgoods.com4.7(143)$24.20L-Tryptophan 500 mg
Natural Wellness Corner4.7(143)$23.00Protocol for Life Balance Clinical Stress Relief 60 Capsules
Supplement First4.8(32)$33.00NOW Foods L- Tryptophan Relaxation Support Capsules
Swanson Health Products4.6(4100)$15.49Protocol For Life Balance 5-HTP 100mg 90 Capsules
Vitacost.com4.8(83)$30.00Protocol For Life Balance L-Carnitine 500 mg 60 Capsules
iHerb4.8(91)$27.00L-Tryptophan Pure Encapsulations
Pure Prescriptions4.6(42)$72.50
Where to Buy Locally
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Golden Athlete butik Sveavägen
4.6 (82)Vitamin & supplements store
Sveavägen 136, 113 50 Stockholm
Golden Athlete butik Uppsala
4.6 (66)Vitamin & supplements store
Hjalmar Brantingsgatan 1, 753 27 Uppsala
Vitamina
5.0 (2)Vitamin & supplements store
Torshamnsgatan 35, 164 40 Kista
Zobr Sweden AB
5.0 (5)Vitamin & supplements store
Östermalmstorg 2, Postbox: 55692, 114 42 Stockholm
MAXAT Nordic
4.8 (46)Vitamin & supplements store
Storgatan 70C, 171 52 Solna
Cellnutrition
5.0 (1)Health food store
Abbedissavägen 19, 746 95 Skokloster
Super Synbiotics
5.0 (1)Vitamin & supplements store
Malmskillnadsgatan 44, 111 57 Stockholm
NutriVision Research & Development Sweden AB: Lipolar Balans
5.0 (3)Vitamin & supplements store
Uppsala Science Park, 751 83 Uppsala
Research & Studies
Oral tryptophan activates duodenal aryl hydrocarbon receptor in healthy subjects: a crossover randomized controlled trial
GH Rueda, N Causada-Calo… - American Journal …, 2024 - journals.physiology.org
… with l-tryptophan supplementation, which is not surprising as this study was performed in healthy … l-Tryptophan supplementation did not affect cytokine production by PBMC with placebo, …
202430 citationsSerotonin, Kynurenine, and Indole Pathways of Tryptophan Metabolism in Humans in Health and Disease
M Holeček - Nutrients, 2026 - mdpi.com
… Many bacteria, including the genera Escherichia, Clostridium, and Bacteroides, hydrolyze TRP by tryptophanase (L-tryptophan indole-lyase) to indole, which exerts beneficial effects on …
202613 citationsL-Tryptophan: Basic Metabolic Functions, Behavioral Research and Therapeutic Indications
DM Richard, MA Dawes, CW Mathias… - International …, 2009 - journals.sagepub.com
… general healthy nutrition. While typical intake for many individuals is approximately 900 to 1000 mg daily, the recommended daily allowance for adults is estimated to be between 250 …
2009981 citationsA systematic review of the effect of L-tryptophan supplementation on mood and emotional functioning
AM Kikuchi, A Tanabe, Y Iwahori - Journal of dietary supplements, 2021 - Taylor & Francis
… This systematic review includes 11 RCTs that examined the effects of TRP intake on positive and negative mood in healthy adult populations. We have targeted healthy adult men and …
2021109 citationsSupplementing healthy women with up to 5.0 g/d of L-tryptophan has no adverse effects
C Hiratsuka, T Fukuwatari, M Sano, K Saito… - The Journal of …, 2013 - academic.oup.com
… intake of the essential amino acid L-tryptophan (L-Trp) have … Indeed, pellagra remains a public health problem in many … the nutritional requirements for L-Trp (300 mg/d in adults) (12) …
201379 citationsTryptophan 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 …
Data sourced from the U.S. National Institutes of Health, Office of Dietary Supplements Dietary Supplement Label Database (DSLD) · Label entered 2017-04-25. DSLD Label ID: 72864. 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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