{
  "dataset": "l-glutamine-cost-by-brand",
  "title": "L-Glutamine Supplements Compared — cost per gram, powder vs capsule, and sport certification",
  "sourcePage": "https://verifiedsupplementdata.com/l-glutamine/best-overall/",
  "license": "CC-BY-4.0",
  "licenseUrl": "https://creativecommons.org/licenses/by/4.0/",
  "attribution": "Verified Supplement Data (2026), L-Glutamine Cost Comparison",
  "dateModified": "2026-07-17",
  "methodology": "L-glutamine is a commodity amino acid: nearly every product is pure micronized/free-form L-glutamine, chemically identical, so brand and price differences are not quality differences. costPerGram = costPerServing / (mg per serving / 1000). \"verdict\": powder-value (commodity powder), powder-nsf (NSF Certified for Sport powder — banned-substance assurance for drug-tested athletes), capsule (1 g/cap, so ~5 capsules for a 5 g dose — a pill burden powders avoid). Typical dose is ~5 g/day (a round, low-risk amount; no single RCT sets it). IMPORTANT evidence context: controlled human evidence does NOT support glutamine as a \"gut healer\" — a Crohn's Cochrane review found insufficient evidence (Akobeng 2016, PMID 26853855) and a meta-analysis found no effect on intestinal permeability at normal doses (Abbasi 2024, PMID 39397201); it had no effect on athletic performance/immunity (Ramezani Ahmadi 2019, PMID 29784526); and high-dose glutamine was associated with INCREASED mortality in critically ill patients (REDOXS, Heyland 2013, PMID 23594003). The one FDA-approved use is reducing sickle-cell crises (Endari; Niihara 2018, PMID 30021096). Avoid in advanced cirrhosis (raises ammonia).",
  "headline": {
    "productsCompared": 14,
    "valuePowders": 9,
    "nsfCertified": 2,
    "capsules": 3,
    "studiedDoseG": 5,
    "cheapestValueBrand": "Naked Nutrition",
    "cheapestValueCostPerGram": 0.034,
    "cheapestNsfBrand": "Klean Athlete",
    "cheapestNsfCostPerGram": 0.132,
    "note": "The molecule is identical across brands. The cheapest commodity powder is the honest default; NSF Certified for Sport (~4x the price) is worth it ONLY for drug-tested athletes; capsules cost more per gram and take ~5 pills for a 5 g dose."
  },
  "columns": [
    "brand",
    "product",
    "slug",
    "form",
    "verdict",
    "gPerServing",
    "servings",
    "price",
    "costPerServing",
    "costPerGram",
    "capsulesToReach5g",
    "thirdParty"
  ],
  "units": {
    "gPerServing": "g L-glutamine per serving",
    "price": "USD",
    "costPerServing": "USD/serving",
    "costPerGram": "USD per gram of L-glutamine"
  },
  "citations": [
    {
      "claim": "Crohn's disease: insufficient evidence; glutamine may not be beneficial (2 RCTs, 42 patients).",
      "source": "Akobeng AK, et al. 2016, Cochrane Database Syst Rev",
      "pmid": "26853855"
    },
    {
      "claim": "No significant effect on intestinal permeability at normal doses (10 trials).",
      "source": "Abbasi F, et al. 2024, Amino Acids",
      "pmid": "39397201"
    },
    {
      "claim": "No effect on athletic performance, immune function, or body composition (25 trials).",
      "source": "Ramezani Ahmadi A, et al. 2019, Clinical Nutrition",
      "pmid": "29784526"
    },
    {
      "claim": "High-dose glutamine was associated with INCREASED mortality in critically ill patients (32.4% vs 27.2%).",
      "source": "Heyland D, et al. 2013 (REDOXS), NEJM",
      "pmid": "23594003"
    },
    {
      "claim": "FDA-approved use: L-glutamine reduced sickle-cell pain crises (median 3 vs 4).",
      "source": "Niihara Y, et al. 2018, NEJM",
      "pmid": "30021096"
    }
  ],
  "products": [
    {
      "brand": "Naked Nutrition",
      "product": "Pure L-Glutamine Powder (1 kg, 200 servings)",
      "slug": "naked-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 200,
      "price": 34.99,
      "costPerServing": 0.17,
      "costPerGram": 0.034,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (3rd-party heavy-metal tested)"
    },
    {
      "brand": "BulkSupplements",
      "product": "L-Glutamine Powder (1 kg)",
      "slug": "bulksupplements-glutamine-1kg",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 200,
      "price": 36.97,
      "costPerServing": 0.18,
      "costPerGram": 0.036,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (3rd-party tested)"
    },
    {
      "brand": "Nutricost",
      "product": "L-Glutamine Powder (500 g)",
      "slug": "nutricost-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 100,
      "price": 22.95,
      "costPerServing": 0.23,
      "costPerGram": 0.046,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (3rd-party tested)"
    },
    {
      "brand": "Sports Research",
      "product": "L-Glutamine Powder (500 g)",
      "slug": "sports-research-glutamine",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 100,
      "price": 24.95,
      "costPerServing": 0.25,
      "costPerGram": 0.05,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (NOT NSF Certified for Sport despite sport branding)"
    },
    {
      "brand": "BulkSupplements",
      "product": "L-Glutamine Powder (500 g)",
      "slug": "bulksupplements-glutamine-500g",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 100,
      "price": 25.97,
      "costPerServing": 0.26,
      "costPerGram": 0.052,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (3rd-party tested)"
    },
    {
      "brand": "NOW Foods",
      "product": "NOW Sports L-Glutamine Pure Powder (1 lb)",
      "slug": "now-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 90,
      "price": 24.17,
      "costPerServing": 0.27,
      "costPerGram": 0.054,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (cGMP)"
    },
    {
      "brand": "MRM Nutrition",
      "product": "MRM L-Glutamine 5000 mg Powder (500 g)",
      "slug": "mrm-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 100,
      "price": 26.99,
      "costPerServing": 0.27,
      "costPerGram": 0.054,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None"
    },
    {
      "brand": "Optimum Nutrition",
      "product": "L-Glutamine Powder (1000 g)",
      "slug": "optimum-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 194,
      "price": 55.99,
      "costPerServing": 0.29,
      "costPerGram": 0.058,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None (NOT NSF Certified for Sport)"
    },
    {
      "brand": "Life Extension",
      "product": "L-Glutamine Powder (100 g)",
      "slug": "life-extension-glutamine-powder",
      "form": "Powder",
      "gPerServing": 2,
      "servings": 50,
      "price": 16.5,
      "costPerServing": 0.33,
      "costPerGram": 0.165,
      "capsulesToReach5g": null,
      "verdict": "powder-value",
      "thirdParty": "None"
    },
    {
      "brand": "Klean Athlete",
      "product": "Klean Glutamine Powder (~490 g)",
      "slug": "klean-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 98,
      "price": 65,
      "costPerServing": 0.66,
      "costPerGram": 0.132,
      "capsulesToReach5g": null,
      "verdict": "powder-nsf",
      "thirdParty": "NSF Certified for Sport"
    },
    {
      "brand": "Thorne",
      "product": "L-Glutamine Powder (513 g, 90 servings)",
      "slug": "thorne-glutamine-powder",
      "form": "Powder",
      "gPerServing": 5,
      "servings": 90,
      "price": 67,
      "costPerServing": 0.74,
      "costPerGram": 0.148,
      "capsulesToReach5g": null,
      "verdict": "powder-nsf",
      "thirdParty": "NSF Certified for Sport"
    },
    {
      "brand": "Horbaach",
      "product": "L-Glutamine 1000 mg (180 Capsules)",
      "slug": "horbaach-glutamine-caps",
      "form": "Capsule",
      "gPerServing": 1,
      "servings": 180,
      "price": 9.99,
      "costPerServing": 0.06,
      "costPerGram": 0.06,
      "capsulesToReach5g": 5,
      "verdict": "capsule",
      "thirdParty": "None"
    },
    {
      "brand": "Optimum Nutrition",
      "product": "L-Glutamine 1000 mg (240 Capsules)",
      "slug": "optimum-glutamine-caps",
      "form": "Capsule",
      "gPerServing": 1,
      "servings": 240,
      "price": 19.99,
      "costPerServing": 0.08,
      "costPerGram": 0.08,
      "capsulesToReach5g": 5,
      "verdict": "capsule",
      "thirdParty": "None"
    },
    {
      "brand": "NOW Foods",
      "product": "NOW Sports L-Glutamine 1000 mg (120 Veg Capsules)",
      "slug": "now-glutamine-caps",
      "form": "Capsule",
      "gPerServing": 1,
      "servings": 120,
      "price": 15.91,
      "costPerServing": 0.13,
      "costPerGram": 0.13,
      "capsulesToReach5g": 5,
      "verdict": "capsule",
      "thirdParty": "None (cGMP)"
    }
  ]
}