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L-Tryptophan 500 mg

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(206 ratings)
Tryptophan 500 mg
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Score82
500 mg of Ajinomoto TryptoPure L-tryptophan offers a focused serotonin-precursor approach with good value, though the formula covers only one pathway.
How scoring works
Quantity:90 Veggie Cap(s) • (90 servings)
Goals:
Stress Relief
Sleep Support
Mood Support

Score 82

500 mg of Ajinomoto TryptoPure L-tryptophan offers a focused serotonin-precursor approach with good value, though the formula covers only one pathway.
How scoring works
$29.19($0.32 per serving)
iHerb
$ 29.19
iHerb
$ 29.19
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Analysis

L-tryptophan supplies a precursor used in serotonin and melatonin production. The 500 mg amount is a practical starting serving in a vegetable capsule.

The TryptoPure source adds clear raw-material differentiation. 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 starting with a moderate tryptophan amount
Best for
  • Evening or mood-support routines
  • Standalone tryptophan supplementation

Pros

  • Provides 500 mg of L-tryptophan
  • Uses branded TryptoPure material
  • Vegetable capsule format
  • Good value

Cons

  • Premium sourcing increases cost in some sizes
  • 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

97 Highest impact

Branded TryptoPure provides useful source-quality differentiation. The tryptophan amount is substantial for targeted supplementation.

Ingredient transparency

85 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 favorable and the aggregate pool is limited. No specific feedback is provided to assess recurring complaints or whether experience matches the intended use.

Value for money

78 High impact

Serving cost is moderate for the disclosed active amount. Branded sourcing adds quality but does not always justify the premium.

Report analysis

Goals

Stress Relief
Stress Relief
Impact
Highest effect
B+ Goal FitA+ Strength of SupportC CoverageA+ Formula Quality
Tryptophan · 500 mg

A branded L-tryptophan amount supports serotonin synthesis and may help the emotional side of stress. Evidence is supportive but less direct and consistent than for established adaptogens or L-theanine.

The pure L-form, clear amount, and absence of competing amino acids are strong formulation features. Tryptophan may interact with SSRIs, SNRIs, MAO inhibitors, or other serotonergic medicines by increasing serotonin effects.

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

Branded TryptoPure L-tryptophan provides a direct precursor for serotonin and melatonin production. The absence of competing amino acids supports its targeted use.

The disclosed amount is practical for initial sleep support, though response varies with diet and individual metabolism. Tryptophan can add to serotonergic effects, so people using serotonin-modulating medicines should seek specific medical guidance before combining them.

Study evidence
Tryptophan Mixed 1 study
Mood Support
Mood Support
Impact
Highest effect
B Goal FitA- Strength of SupportC- CoverageA+ Formula Quality

L-tryptophan is a direct serotonin precursor and may support mood when precursor availability is limiting. The branded source and focused amount provide strong purity and dose confidence.

The single-active design gives useful depth in one neurotransmitter pathway but no broader stress or structural support. L-tryptophan may compound serotonergic antidepressants and can cause drowsiness in some users.

Study evidence
Tryptophan Mixed 1 study

Ingredients

IngredientAmount per serving
Ajinomoto TryptoPure L-Tryptophan
500 mg
Adults 18–50 Vegetarian
Report overview
Tryptophan (L-Tryptophan) · 500 mg OverallScore96
A+ Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyB+ Value

Branded TryptoPure L-Tryptophan provides a strong purity signal in a capsule format. No competing large neutral amino acids are present, supporting targeted brain uptake. The clearly listed 500 mg amount falls within the targeted support range, and cost efficiency is favorable.

View ingredientView products
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83 Performance

L-Tryptophan 1000 mg

AN Amazing Nutrition Amazing Formulas
The standalone L-form is appropriate, though a tablet is a less flexible delivery format. The supplied analysis indicates a stronger formulation than the original, without relying on an exact price comparison.
83 Performance

L-Tryptophan 500 mg

Jarrow Formulas
The standalone L-form avoids competing amino acids, but source-grade details are not supplied. The supplied analysis indicates a stronger formulation than the original, without relying on an exact price comparison.
82 Performance

L-Tryptophan Powder

NOW
The standalone powder avoids competing amino acids and allows flexible measuring. The supplied analysis indicates a stronger formulation than the original, without relying on an exact price comparison.
85 Budget

L-Tryptophan 500 mg

Doctor's Best
Branded TryptoPure provides useful source-quality differentiation. Its supplied serving cost is lower than the original’s, while the tryptophan-focused formula remains relevant.
84 Budget

L-Tryptophan 500 mg

Life Extension
The standalone L-form avoids competing amino acids, but source-grade details are not supplied. Its supplied serving cost is lower than the original’s, while the tryptophan-focused formula remains relevant.
83 Budget

L-Tryptophan 500 mg

Swanson
The standalone L-form avoids competing amino acids, but source-grade details are not supplied. Its supplied serving cost is lower than the original’s, while the tryptophan-focused formula remains relevant.
82 Value

L-Tryptophan 1000 mg

AN Amazing Nutrition Amazing Formulas
The standalone L-form is appropriate, though a tablet is a less flexible delivery format. Its formulation quality and lower supplied serving cost create a favorable value balance versus the original.
82 Value

Sleep Nighttime Powder

youtheory
Glycine, L-theanine, magnesium citrate, tryptophan, 5-HTP, and low-dose melatonin create a well-dosed nighttime formula. Its formulation quality may justify the higher supplied serving cost, though the value advantage depends on prioritizing the ingredient profile.
78 Value

L-Tryptophan 500 mg

Advanced Nutrition by Zahler
The standalone L-form avoids competing amino acids, but source-grade details are not supplied. Its formulation quality and lower supplied serving cost create a favorable value balance versus the original.
Report alternatives

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