L-Tryptophan 500 mg®

Objective insights generated automatically from the official DSLD label — a quick, factual read of how this product is formulated and disclosed.

This analysis is generated algorithmically from label data for educational reference only. It is not a product endorsement, ranking, or medical advice.

Serving Size: 1 Vegetarian Capsule(s) · 1–3 per day

Not Present

• 

  Life Extension L- Tryptophan 500 mg 90 Vegetarian Capsules

  Vitacost.com4.7(505)

  $24.75
• 

  Life Extension Tryptophan Plus Capsules

  Walmart - Life Extension Buyers Club4.7(629)

  $24.00
• 

  Source Naturals L Tryptophan

  Life Extension4.6(1100)

  $16.88
• 

  Life Extension L Tryptophan 90 Vegan Capsules

  GoSupps.com

  $104.99
• 

  NOW Foods L- Tryptophan Relaxation Support Capsules

  Target4.6(4100)

  $16.99
• 

  Now Foods L-Tryptophan 500 mg

  DPS Nutrition4.6(5600)

  $20.99
• 

  Best Naturals L-Tryptophan mg 60

  Walmart - Best Naturals4.5(135)

  $12.99
• 

  Swanson L- Tryptophan 500 mg 90 Veggie Capsules

  iHerb4.7(2000)

  $13.69

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• Serotonin, 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 citations

• Tryptophan: biochemical and health implications

  H Sidransky - 2001 - api.taylorfrancis.com

  … L-tryptophan, an important indispensable amino acid, may act. Overall, it becomes apparent that L-tryptophan … The role of L-tryptophan in health and disease has become apparent from …

  200146 citations

• 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

  … ) intake while containing less than 500 mg of l-tryptophan per day. Subjects were provided … l-tryptophan supplementation, which is not surprising as this study was performed in healthy …

  202430 citations

• Serum metabolic and microbial profiling yields insights into promoting effect of tryptophan‐related metabolites for health longevity in centenarians

  X Qiu, C Mu, J Hu, J Yu, W Tang, Y Liu, Y Huang, Y Lu… - Imeta, 2025 - Wiley Online Library

  … 5-Hydroxy-L-tryptophan, L-Formylkynurenine and L-Tryptophan. 5-… 5-MIAA is a downstream product of L-tryptophan metabolism, … Therefore, the potential of 5-MIAA for life extension was …

  202515 citations

• A 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 citations

• L-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 citations

Data sourced from the U.S. National Institutes of Health, Office of Dietary Supplements Dietary Supplement Label Database (DSLD) · Label entered 2020-08-23. DSLD Label ID: 231998. 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.