{
  "dataset": "milk-thistle-cost-by-brand",
  "title": "Milk Thistle (Silymarin) Supplements Compared — cost per serving, silymarin standardization, and cost per 100 mg of actual silymarin",
  "sourcePage": "https://verifiedsupplementdata.com/milk-thistle/best-overall/",
  "license": "CC-BY-4.0",
  "licenseUrl": "https://creativecommons.org/licenses/by/4.0/",
  "attribution": "Verified Supplement Data (2026), Milk Thistle Cost & Standardization Comparison",
  "dateModified": "2026-07-16",
  "methodology": "The active compound in milk thistle is silymarin, a flavonolignan complex (main component silibinin). Quality extracts are standardized to a silymarin percentage (pharmacopeial ~70-80%), so actual active mg = extract mg x silymarin %. Cheap products headline a large raw number (\"1000 mg\", \"3000 mg\", \"4:1 extract\", \"full-spectrum\") with NO silymarin % — so actual active content is unknown. Independent testing (ConsumerLab, not peer-reviewed) found silymarin per daily serving varying ~2,800% (from 17.4 to 498 mg), with 2 of 6 products at only 40-60% of labeled silymarin; a peer-reviewed analysis found 35-125% of declared silymarin, with 4 of 26 samples below 50% (Fenclova 2019, PMID 31366891). \"verdict\": silymarin-standardized (discloses a silymarin % -> active mg computable), phospholipid-form (silybin-phosphatidylcholine / Siliphos -> higher absorption, not comparable to raw-herb mg), undisclosed (raw extract mg / 4:1 / full-spectrum, no % -> active unknown). costPer100mgSilymarin = costPerServing / (disclosed silymarin mg / 100); null where undisclosed. The clinically studied dose is ~200 mg silymarin 2-3x/day (~420 mg/day). Note: IV silibinin (Legalon SIL) is an accepted hospital antidote for Amanita mushroom poisoning, which is NOT the same as an oral capsule; and the Cochrane review found no confirmed liver-mortality benefit in high-quality trials.",
  "headline": {
    "productsCompared": 12,
    "discloseSilymarinPct": 5,
    "undisclosed": 5,
    "cheapestPer100mgSilymarin": 0.07,
    "cheapestPer100mgSilymarinBrand": "NOW Foods",
    "note": "Of the products compared, 5 disclose a silymarin % (so you can price the actual active); the rest headline a raw \"milligram\" or \"4:1 / full-spectrum\" figure with no silymarin content — cost per unit of active is incomputable for them."
  },
  "columns": [
    "brand",
    "product",
    "slug",
    "form",
    "extractMgPerServing",
    "silymarinPct",
    "silymarinMgPerServing",
    "servings",
    "price",
    "costPerServing",
    "costPer100mgSilymarin",
    "verdict",
    "thirdParty"
  ],
  "units": {
    "extractMgPerServing": "mg milk thistle extract (marketed)",
    "silymarinMgPerServing": "mg silymarin (computed)",
    "price": "USD",
    "costPerServing": "USD/day",
    "costPer100mgSilymarin": "USD per 100 mg silymarin"
  },
  "citations": [
    {
      "claim": "Silymarin content varied ~2,800% across products (17.4-498 mg/serving); 2 of 6 at 40-60% of label.",
      "source": "ConsumerLab.com (independent testing; not peer-reviewed)"
    },
    {
      "claim": "Commercial milk thistle supplements contained 35-125% of declared silymarin; 4 of 26 below 50%.",
      "source": "Fenclova M, et al. 2019, Sci Rep",
      "pmid": "31366891"
    },
    {
      "claim": "In NAFLD/NASH, silymarin significantly reduced ALT and AST (26 RCTs, 2,375 patients).",
      "source": "Li S, et al. 2024, Ann Hepatol",
      "pmid": "38579127"
    },
    {
      "claim": "Cochrane review: no significant effect on all-cause mortality; liver-mortality benefit was NOT significant in high-quality trials.",
      "source": "Rambaldi A, et al. 2007, Cochrane Database Syst Rev",
      "pmid": "17943794"
    },
    {
      "claim": "IV silibinin (Legalon SIL) in amatoxin poisoning: 1,491 cases, 93% survival (a hospital IV protocol, not an oral capsule).",
      "source": "Mengs U, et al. 2012, Curr Pharm Biotechnol",
      "pmid": "22352731"
    }
  ],
  "products": [
    {
      "brand": "NOW Foods",
      "product": "Silymarin Milk Thistle Extract 300 mg, Double Strength (100 Capsules)",
      "slug": "now-silymarin-2x",
      "form": "capsule",
      "extractMgPerServing": 300,
      "silymarinPct": 80,
      "silymarinMgPerServing": 240,
      "servings": 100,
      "price": 17.35,
      "costPerServing": 0.17,
      "costPer100mgSilymarin": 0.07,
      "verdict": "silymarin-standardized",
      "thirdParty": "None (GMP)"
    },
    {
      "brand": "Jarrow Formulas",
      "product": "Milk Thistle 150 mg, 30:1 Standardized (100 Capsules)",
      "slug": "jarrow-milk-thistle",
      "form": "capsule",
      "extractMgPerServing": 150,
      "silymarinPct": 80,
      "silymarinMgPerServing": 120,
      "servings": 100,
      "price": 16.51,
      "costPerServing": 0.17,
      "costPer100mgSilymarin": 0.14,
      "verdict": "silymarin-standardized",
      "thirdParty": "None (Non-GMO)"
    },
    {
      "brand": "Solaray",
      "product": "Milk Thistle One Daily, Seed Extract 350 mg (60 Capsules)",
      "slug": "solaray-milk-thistle",
      "form": "capsule",
      "extractMgPerServing": 350,
      "silymarinPct": 80,
      "silymarinMgPerServing": 280,
      "servings": 60,
      "price": 30.64,
      "costPerServing": 0.51,
      "costPer100mgSilymarin": 0.18,
      "verdict": "silymarin-standardized",
      "thirdParty": "None (lab verified)"
    },
    {
      "brand": "Pure Encapsulations",
      "product": "Silymarin 250 mg (120 Capsules)",
      "slug": "pure-encapsulations-silymarin",
      "form": "capsule",
      "extractMgPerServing": 250,
      "silymarinPct": 80,
      "silymarinMgPerServing": 200,
      "servings": 120,
      "price": 45,
      "costPerServing": 0.38,
      "costPer100mgSilymarin": 0.19,
      "verdict": "silymarin-standardized",
      "thirdParty": "None (hypoallergenic)"
    },
    {
      "brand": "Nature's Way",
      "product": "Milk Thistle, 175 mg Seed Extract, 80% Silymarin (120 Capsules)",
      "slug": "natures-way-milk-thistle",
      "form": "capsule",
      "extractMgPerServing": 175,
      "silymarinPct": 80,
      "silymarinMgPerServing": 140,
      "servings": 120,
      "price": 31.75,
      "costPerServing": 0.26,
      "costPer100mgSilymarin": 0.19,
      "verdict": "silymarin-standardized",
      "thirdParty": "None (TRU-ID authenticated)"
    },
    {
      "brand": "Thorne",
      "product": "Milk Thistle Phytosome (Siliphos) (90 Capsules)",
      "slug": "thorne-milk-thistle-phytosome",
      "form": "capsule",
      "extractMgPerServing": null,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 90,
      "price": 48,
      "costPerServing": 0.53,
      "costPer100mgSilymarin": null,
      "verdict": "phospholipid-form",
      "thirdParty": "Third-party certified (Thorne)"
    },
    {
      "brand": "Thorne",
      "product": "S.A.T. — Milk Thistle + Artichoke + Turmeric (60 Capsules)",
      "slug": "thorne-sat",
      "form": "capsule",
      "extractMgPerServing": null,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 60,
      "price": 47,
      "costPerServing": 0.78,
      "costPer100mgSilymarin": null,
      "verdict": "phospholipid-form",
      "thirdParty": "Third-party certified (Thorne)"
    },
    {
      "brand": "Swanson",
      "product": "Full Spectrum Milk Thistle 500 mg (100 Capsules)",
      "slug": "swanson-milk-thistle",
      "form": "capsule",
      "extractMgPerServing": 500,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 100,
      "price": 11.09,
      "costPerServing": 0.11,
      "costPer100mgSilymarin": null,
      "verdict": "undisclosed",
      "thirdParty": "None"
    },
    {
      "brand": "Horbaach",
      "product": "Milk Thistle 3000 mg, 4:1 Extract (300 Capsules)",
      "slug": "horbaach-milk-thistle-3000",
      "form": "capsule",
      "extractMgPerServing": 3000,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 150,
      "price": 16.99,
      "costPerServing": 0.11,
      "costPer100mgSilymarin": null,
      "verdict": "undisclosed",
      "thirdParty": "None"
    },
    {
      "brand": "Nature's Bounty",
      "product": "Milk Thistle 1000 mg, Rapid Release Softgels (50 ct)",
      "slug": "natures-bounty-milk-thistle-1000",
      "form": "softgel",
      "extractMgPerServing": 1000,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 50,
      "price": 9.5,
      "costPerServing": 0.19,
      "costPer100mgSilymarin": null,
      "verdict": "undisclosed",
      "thirdParty": "None"
    },
    {
      "brand": "Himalaya",
      "product": "Milk Thistle Liver Support 350 mg (60 Capsules)",
      "slug": "himalaya-milk-thistle",
      "form": "capsule",
      "extractMgPerServing": 350,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 60,
      "price": 26,
      "costPerServing": 0.43,
      "costPer100mgSilymarin": null,
      "verdict": "undisclosed",
      "thirdParty": "USDA Organic + Non-GMO Verified"
    },
    {
      "brand": "Gaia Herbs",
      "product": "Milk Thistle Seed, Liquid Phyto-Caps (120 Capsules)",
      "slug": "gaia-milk-thistle",
      "form": "capsule",
      "extractMgPerServing": null,
      "silymarinPct": null,
      "silymarinMgPerServing": null,
      "servings": 40,
      "price": 51.29,
      "costPerServing": 1.28,
      "costPer100mgSilymarin": null,
      "verdict": "undisclosed",
      "thirdParty": "None"
    }
  ]
}