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L-Glutamine Pure Powder

Best Naturals
4.7
★ ★ ★ ★ ★
(274 ratings)
Glutamine 5000 mg
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Score84
A practical gram-level powder avoids pill burden, with missing purity and micronization details as the main trade-offs.
How scoring works
Quantity:1 lb(s) • (90 servings)
Goals:
Digestive Health
Immunity

Score 84

A practical gram-level powder avoids pill burden, with missing purity and micronization details as the main trade-offs.
How scoring works
$24.55($0.27 per serving)
iHerb
$ 24.55
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Analysis

A 5000 mg serving reaches a meaningful gram-level intake that may support intestinal-cell fuel during physiological stress. The focused powder is easy to scale and contains no competing active ingredients.

The supplied data do not identify a premium purity grade or micronized processing. Those omissions do not change the disclosed amount but limit comparison with higher-specification powders.

A one-teaspoon serving is convenient for daily use. The large package provides excellent cost efficiency. The product supports one gut-barrier and metabolic pathway rather than fiber, enzymes, motility, or microbiome diversity.

Who is it for
  • Adults seeking gram-level L-glutamine
  • People who prefer powders to multiple capsules
  • Users focused on a single amino acid
Best for
  • Gut-barrier support during physiological stress
  • Flexible gram-level dosing
  • Mixing into water or another drink

Pros

  • 5000 mg serving
  • Single-ingredient powder
  • Easy to scale

Cons

  • No premium purity grade
  • Micronization is not stated
  • No premium purity grade is stated.

Nutrient quality

90 Highest impact

Clear L-glutamine labeling and the powder format support straightforward use. The powder provides a substantial targeted glutamine serving, while the substantial amount remains within common supplemental use.

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Ingredient transparency

83 Highest impact

The active amount is disclosed without a hidden blend. Intake directions and inactive ingredients are not supplied.

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Customer satisfaction

64 Moderate impact

The supplied average rating is strong and comes from a limited rating pool. No firsthand experiences or recurring complaint details were provided, so consistency remains uncertain.

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Value for money

97 Highest impact

A substantial powder serving and low cost create excellent value. The scalable format compares very well for targeted use.

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Goals

Digestive Health
Digestive Health
Impact
Highest effect
A- Goal FitA+ Strength of SupportC- CoverageA+ Formula Quality
Glutamine · 5000 mg

L-glutamine directly supplies fuel used by intestinal cells and is provided at a substantial disclosed amount. The simple powder reaches a practical gram-level serving without a proprietary blend.

The product offers excellent depth for gut-lining support but does not address fiber, enzymes, motility, or the microbiome. Missing purity-grade and micronization details are modest limitations.

Study evidence
Glutamine Supportive 37 studies
Immunity
Immunity
Impact
High effect
D Goal FitA- Strength of SupportD+ CoverageA Formula Quality

L-glutamine at 5 g may support intestinal barrier cells and immune-cell fuel during heavy physical stress or inadequate intake. The pure powder provides a substantial, fully disclosed amount without competing ingredients.

Evidence for improving immune outcomes in generally healthy people is limited, so it is not a direct broad-spectrum immunity product. The formula covers only one barrier and metabolic pathway.

Study evidence
Glutamine Supportive 36 studies

Ingredients

IngredientAmount per serving
L-Glutamine
5000 mg
Gluten Free Adults 18–50 Dairy Free Sugar Free
Report overview
Glutamine · 5000 mg OverallScore86
C Active Ingredient Quality & BioavailabilityA+ Dose, Safety & Label TransparencyA+ Value

The full serving delivers a substantial amount of clearly disclosed L-glutamine in a simple powder. The standard ingredient lacks a named purity grade, and the label does not say it is micronized. One-teaspoon dosing is convenient, while the amount supplied for the cost is highly economical.

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Loading alternative details
82 Performance

L-Glutamine Powder

Bluebonnet
<p>Its label clearly provides 5000 mg of L-Glutamine, Powder, making it a more clearly defined glutamine option. Compared with the original, its ingredient and goal alignment is stronger, although the input does not provide independent testing or absorption evidence.</p>
78 Performance

L-Glutamine Powder

DaVinci Laboratories Of Vermont
<p>Its label clearly provides 5000 mg of L-Glutamine, making it a more clearly defined glutamine option. Compared with the original, its ingredient and goal alignment is stronger, although the input does not provide independent testing or absorption evidence.</p>
80 Performance

Theracurmin & L-Glutamine

Natural Factors CurcuminRich
<p>Its label clearly provides 5000 mg of L-Glutamine, Micronized, making it a more clearly defined glutamine option. Compared with the original, its ingredient and goal alignment is stronger, although the input does not provide independent testing or absorption evidence.</p>
84 Budget

Glutamine 300

PS ProSupps
<p>Its label clearly provides 4500 mg of L-Glutamine, preserving relevant glutamine coverage. Compared with the original, it lowers the serving cost, although the input does not provide independent testing or absorption evidence.</p>
83 Budget

Micronized L-Glutamine 1000 mg

Natural Factors
<p>Its label clearly provides 1000 mg of L-Glutamine, Micronized, preserving relevant glutamine coverage. Compared with the original, it lowers the serving cost, although the input does not provide independent testing or absorption evidence.</p>
82 Budget

L-Glutamine

Jarrow Formulas
<p>Its label clearly provides 1000 mg of L-Glutamine, preserving relevant glutamine coverage. Compared with the original, it lowers the serving cost, although the input does not provide independent testing or absorption evidence.</p>
84 Value

Glutamine Pure Powder 5000 mg (5 g)

Country Life
<p>Its label clearly provides 5000 mg of L-Glutamine, keeping the formula relevant to glutamine. Compared with the original, the somewhat higher serving cost and ingredient detail create a useful quality-to-cost balance, although the input does not provide independent testing or absorption evidence.</p>
71 Value

IntestiNew

Renew Life
<p>Its label clearly provides 5000 mg of L-Glutamine, keeping the formula relevant to glutamine. Compared with the original, the somewhat higher serving cost and ingredient detail create a useful quality-to-cost balance, although the input does not provide independent testing or absorption evidence.</p>
80 Value

L-Glutamine 1000 mg

Solgar
<p>Its label clearly provides 2000 mg of L-Glutamine, keeping the formula relevant to glutamine. Compared with the original, the somewhat higher serving cost and ingredient detail create a useful quality-to-cost balance, although the input does not provide independent testing or absorption evidence.</p>
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Sources

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

  1. Effect of perioperative glutamine-enriched nutritional support on patients with colorectal cancer: A systematic review and meta-analysis.
    Huang Y; Yang XZ; Qin SH; Zhang T; Xie M; Wang JW · World journal of gastrointestinal surgery · 2026
    Meta-analysis1,643 participants27 studies pooledDigestive Health Immunity forGlutamine
  2. Glutamine prevents diarrhea in colorectal cancer patients undergoing chemotherapy or chemoradiotherapy: a meta-analysis.
    Chen L; Wang D; Meng C; Sun H; Li R; Miao G; Liu P · BMC gastroenterology · 2025
    Meta-analysis311 participants5 studies pooledDigestive Health forGlutamine
  3. Glutamine supplementation reduces markers of intestinal permeability during running in the heat in a dose-dependent manner.
    Pugh JN; Sage S; Hutson M; Doran DA; Fleming SC; Highton J; Morton JP; Close GL · European journal of applied physiology · 2018
    Randomized trial10 participantsDigestive Health forGlutamine
  4. Effect of glutamine supplementation on diarrhea, interleukin-8 and secretory immunoglobulin A in children with acute diarrhea.
    Yalçin SS; Yurdakök K; Tezcan I; Oner L · Journal of pediatric gastroenterology and nutrition · 2004
    Randomized trial128 participantsDigestive Health forGlutamine
  5. Improvement of intestinal permeability with alanyl-glutamine in HIV patients: a randomized, double blinded, placebo-controlled clinical trial.
    Leite RD; Lima NL; Leite CA; Farhat CK; Guerrant RL; Lima AA · Arquivos de gastroenterologia · 2013
    Randomized trial46 participantsDigestive Health forGlutamine
  6. Meta-analysis of Glutamine on Immune Function and Post-Operative Complications of Patients With Colorectal Cancer.
    Yang T; Yan X; Cao Y; Bao T; Li G; Gu S; Xiong K; Xiao T · Frontiers in nutrition · 2021
    Meta-analysis2,201 participants31 studies pooledImmunity forGlutamine
  7. Efficacy of Glutamine in Treating Severe Acute Pancreatitis: A Systematic Review and Meta-Analysis.
    Dong S; Zhao Z; Li X; Chen Z; Jiang W; Zhou W · Frontiers in nutrition · 2023
    Meta-analysis1,201 participants30 studies pooledImmunity forGlutamine
  8. Decreased mortality and infectious morbidity in adult burn patients given enteral glutamine supplements: a prospective, controlled, randomized clinical trial.
    Garrel D; Patenaude J; Nedelec B; Samson L; Dorais J; Champoux J; D'Elia M; Bernier J · Critical care medicine · 2003
    Randomized trial45 participantsImmunity forGlutamine
  9. Glutamine administration reduces Gram-negative bacteremia in severely burned patients: a prospective, randomized, double-blind trial versus isonitrogenous control.
    Wischmeyer PE; Lynch J; Liedel J; Wolfson R; Riehm J; Gottlieb L; Kahana M · Critical care medicine · 2001
    Randomized trial26 participantsImmunity forGlutamine