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L-Tryptophan Powder

NOW
4.3
★ ★ ★ ★ ★
(585 ratings)
Tryptophan 950 mg
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Score82
950 mg of L-tryptophan offers a focused serotonin-precursor approach with excellent value, though the formula covers only one pathway.
How scoring works
Quantity:2 Liquid(s) • (57 servings)
Goals:
Stress Relief
Sleep Support
Mood Support

Score 82

950 mg of L-tryptophan offers a focused serotonin-precursor approach with excellent value, though the formula covers only one pathway.
How scoring works
$13.90($0.24 per serving)
Pure Formulas
$ 21.76
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$ 23.55
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$ 20.80
iHerb
$ 22.03
Amazon
$ 18.73
Daily Vita
$ 13.90
Daily Vita
$ 16.00
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Analysis

L-tryptophan supplies a precursor used in serotonin and melatonin production. The 950 mg amount is substantial for targeted use in a powder.

The generic source does not disclose purity grade or fermentation details. Effects can vary with timing, diet, and individual metabolism.

No competing amino acids are listed, which supports focused timing away from protein-heavy meals. The formula is focused on one neurotransmitter pathway and does not provide broad sleep, stress, or mood coverage.

Who is it for
  • Adults seeking targeted sleep or mood support
  • Users comfortable with a substantial tryptophan serving
Best for
  • Evening or mood-support routines
  • Standalone tryptophan supplementation

Pros

  • Provides 950 mg of L-tryptophan
  • Contains no competing amino acids
  • Powder format
  • Excellent value

Cons

  • Purity and fermentation details are not disclosed
  • Covers only one neurotransmitter pathway
  • Response may depend on meal timing and individual metabolism

Warnings

  • Do not combine L-tryptophan with SSRIs, SNRIs, MAO inhibitors, tramadol, triptans, or other serotonin-raising medicines without prescriber guidance.
  • Seek urgent care for agitation, confusion, heavy sweating, tremor, or a rapid heartbeat after a serotonergic combination because these can signal excessive serotonin.
  • L-tryptophan may cause drowsiness, so avoid driving or other alertness-dependent tasks until its effects are clear.

Nutrient quality

93 Highest impact

The standalone powder avoids competing amino acids and allows flexible measuring. The tryptophan amount is substantial for targeted supplementation.

Ingredient transparency

83 Highest impact

Every listed active has an individual amount and no proprietary blend hides key doses. Daily directions and the complete inactive-ingredient list are not supplied.

Customer satisfaction

63 Moderate impact

The supplied average is mixed and the aggregate pool is moderate. No specific feedback is provided to assess recurring complaints or whether experience matches the intended use.

Value for money

86 Highest impact

Serving cost is moderate for the disclosed active amount. The focused design avoids paying for unnecessary active ingredients.

Report analysis

Goals

Stress Relief
Impact
Highest effect
B+ Goal FitA Strength of SupportC+ CoverageA+ Formula Quality
Tryptophan · 950 mg

L-tryptophan supports serotonin synthesis and is supplied at a high-potency amount suited to targeted mood or sleep support. The standalone powder avoids competing amino acids and allows flexible timing.

The generic source lacks a stated purity or fermentation standard, which limits ingredient-quality assurance. Combining tryptophan with SSRIs, MAO inhibitors, or other serotonin-raising medicines may increase the risk of serotonin toxicity.

Study evidence
Sleep Support
Impact
Highest effect
B+ Goal FitA- Strength of SupportC CoverageA+ Formula Quality

The 950 mg L-tryptophan amount is well aligned with the supplied dose guidance and may support production of serotonin and melatonin. Human evidence is reasonably supportive for sleep, though effects can vary with timing and dietary competition.

The standalone powder avoids competing amino acids and clearly states the active amount, but no branded source or purity grade is identified. The substantial evening dose may cause drowsiness, so it should be used only when reduced alertness is acceptable.

Study evidence
Tryptophan Mixed 1 study
Mood Support
Impact
High effect
B- Goal FitB Strength of SupportD CoverageB Formula Quality

L-tryptophan directly supplies a serotonin precursor and has credible mood relevance. The 950 mg amount is clearly disclosed.

A focused dose may help selected users, but the formula lacks vitamin B6 or another conversion cofactor. Combining tryptophan with SSRIs, MAO inhibitors, or other serotonergic agents can raise serotonin-syndrome risk.

Study evidence
Tryptophan Mixed 1 study

Ingredients

IngredientAmount per serving
L-Tryptophan
950 mg
Gluten Free Adults 18–50 Vegan Dairy Free Vegetarian
Report overview
Tryptophan · 950 mg OverallScore88
B- Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyA+ Value

The standalone powder provides a high-potency amount without competing amino acids, which supports flexible timing and absorption. Its source and purity grade are not disclosed, so active quality is less certain than with a branded or pharmaceutical-grade material. The exact amount is clearly stated, and the cost per effective amount is highly economical.

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Sources

Published studies used for the product analysis and the top-ranked studies for each ingredient and goal.

  1. A systematic review of the effect of L-tryptophan supplementation on mood and emotional functioning
    Kikuchi AM, Tanabe A, Iwahori Y · Journal of Dietary Supplements · 2021
    Systematic review11 studies pooledMood Support forTryptophan
  2. The impact of tryptophan supplementation on sleep quality: a systematic review, meta-analysis, and meta-regression
    Clarinda N Sutanto, Wen Wei Loh, Jung Eun Kim · Nutrition Reviews · 2022
    Meta-analysis4 studies pooledSleep Support forTryptophan