{
  "name": "Magnesium Sleep-Trial Doses and Cost per 200 mg Elemental Magnesium",
  "license": "https://creativecommons.org/licenses/by/4.0/",
  "priceNote": "Every price and cost here is the brand list price (priceUsd = listPriceUsd), not an Amazon price; prices on Amazon differ. QA round 2, 2026-10-15.",
  "attribution": "Verified Supplement Data, https://verifiedsupplementdata.com/magnesium/dosage-for-sleep/",
  "dateModified": "2026-10-15",
  "sleepDoseSummary": "Sleep trials of plain magnesium used 250 to 729 mg of magnesium a day (Schuster 2025 250 mg as bisglycinate; Mah 2021 pooled 320, 500 and 729 mg). L-threonate trials are separate: 1 to 2 g of the compound, about 72 to 144 mg of magnesium.",
  "sleepTrials": [
    {
      "pmid": "40918053",
      "firstAuthor": "Schuster",
      "year": 2025,
      "design": "randomized, double-blind, placebo-controlled",
      "participants": 155,
      "population": "adults 18-65 reporting poor sleep",
      "form": "magnesium bisglycinate",
      "elementalMgPerDay": 250,
      "weeks": 4,
      "outcome": "Insomnia Severity Index change -3.9 (magnesium) vs -2.3 (placebo), p = 0.049, Cohen's d = 0.2"
    },
    {
      "pmid": "23853635",
      "firstAuthor": "Abbasi",
      "year": 2012,
      "design": "randomized, double-blind, placebo-controlled",
      "participants": 46,
      "population": "older adults with primary insomnia",
      "form": "magnesium oxide",
      "elementalMgPerDay": 500,
      "weeks": 8,
      "outcome": "ISI, sleep efficiency and sleep onset latency improved; total sleep time not significant"
    },
    {
      "pmid": "21199787",
      "firstAuthor": "Nielsen",
      "year": 2010,
      "design": "randomized, double-blind, placebo-controlled",
      "participants": 100,
      "population": "adults over 51 with poor quality sleep",
      "form": "magnesium citrate",
      "elementalMgPerDay": 320,
      "weeks": 7,
      "outcome": "sleep quality scores improved about as much on placebo; magnesium raised blood magnesium in people who started low"
    },
    {
      "pmid": "12163983",
      "firstAuthor": "Held",
      "year": 2002,
      "design": "randomized, placebo-controlled",
      "participants": 12,
      "population": "adults 60 to 80",
      "form": "effervescent magnesium tablets",
      "elementalMgPerDay": 729,
      "weeks": null,
      "outcome": "up to 30 mmol a day for 20 days; more slow-wave sleep on EEG than placebo"
    },
    {
      "pmid": "33865376",
      "firstAuthor": "Mah",
      "year": 2021,
      "design": "systematic review and meta-analysis of 3 RCTs",
      "participants": 151,
      "population": "older adults with insomnia",
      "form": "oral magnesium, mixed",
      "elementalMgPerDay": null,
      "weeks": null,
      "outcome": "sleep onset latency -17.36 min (95% CI -27.27 to -7.44); total sleep time +16.06 min, not significant; low to very low quality evidence"
    }
  ],
  "nihLimits": {
    "rdaMgPerDayAdults": {
      "min": 310,
      "max": 420,
      "note": "by age and sex"
    },
    "rdaMgPerDay": {
      "women": 320,
      "men": 420,
      "note": "adults 31 and older (old key, kept)"
    },
    "supplementalUpperLimitMgPerDay": 350,
    "note": "350 mg/day UL applies to SUPPLEMENTAL elemental magnesium only, not dietary."
  },
  "labelCensus": {
    "source": "NIH Dietary Supplement Label Database (DSLD) v9",
    "sourceUrl": "https://dsld.od.nih.gov/",
    "retrievedOn": "2026-08-29",
    "labelsOnMarket": 39884,
    "labelsRetrieved": 833,
    "labelsWithDose": 825,
    "labelsWithDirections": 826,
    "brands": 276,
    "labelsWithDailyDirection": null,
    "oldKeysNote": "Kept for readers of the old keys (2026-10-15). Census keys set to null were retired when the site moved to one label set (labels with glycinate or bisglycinate on the panel); see the populated keys beside them.",
    "medianElementalMgPerServing": 250,
    "medianElementalMgPerDayAsDirected": 399,
    "medianDirectedExceedsServing": true,
    "formCountMethod": "a label is counted once for each magnesium form its Supplement Facts panel names",
    "labelsNamingOxide": 244,
    "labelsNamingGlycinateOrBisglycinate": 94,
    "validation": {
      "method": "split-half by DSLD read order",
      "checked": 6,
      "held": 3,
      "failed": [
        "most labels as directed exceed the UL",
        "most of the market sells above the typical dose",
        "a large share sells above the studied range"
      ]
    },
    "notPublished": [
      "most labels as directed exceed the UL",
      "most of the market sells above the typical dose",
      "a large share sells above the studied range"
    ]
  },
  "costPer200Mg": [
    {
      "name": "BulkSupplements Magnesium Glycinate Powder (500 g)",
      "brand": "BulkSupplements.com",
      "elementalMgPerServing": 300,
      "servingSize": "2.2 g powder (3/4 tsp)",
      "servingsPerContainer": 227,
      "priceUsd": 21.97,
      "listPriceUsd": 21.97,
      "priceBasis": "brand list price",
      "priceCheckedOn": "2026-10-14",
      "priceVerifiedOn": "2026-11-06",
      "amazonPriceUsd": 22.97,
      "costPer200MgUsd": 0.128,
      "certification": "NSF/ANSI 173 (glycinate + oxide blend)",
      "nihDsldId": null,
      "availability": "ok"
    },
    {
      "name": "Doctor's Best High Absorption Magnesium",
      "brand": "Doctor's Best",
      "elementalMgPerServing": 200,
      "servingSize": "2 tablets",
      "servingsPerContainer": 120,
      "priceUsd": 23.99,
      "listPriceUsd": 23.99,
      "priceBasis": "brand list price",
      "priceCheckedOn": "2026-10-14",
      "priceVerifiedOn": "2026-11-06",
      "amazonPriceUsd": 23.99,
      "costPer200MgUsd": 0.2,
      "certification": "None",
      "nihDsldId": null,
      "availability": "ok"
    },
    {
      "name": "Thorne Magnesium Glycinate (90 capsules)",
      "brand": "Thorne",
      "elementalMgPerServing": 120,
      "servingSize": "1 capsule",
      "servingsPerContainer": 90,
      "priceUsd": 26,
      "listPriceUsd": 26,
      "priceBasis": "brand list price",
      "priceCheckedOn": "2026-10-14",
      "priceVerifiedOn": "2026-11-06",
      "amazonPriceUsd": 26,
      "costPer200MgUsd": 0.481,
      "certification": "NSF/ANSI 173",
      "nihDsldId": null,
      "availability": "ok"
    },
    {
      "name": "Nature Made Magnesium Glycinate 200mg",
      "brand": "Nature Made",
      "elementalMgPerServing": 200,
      "servingSize": "2 capsules",
      "servingsPerContainer": 30,
      "priceUsd": 21.99,
      "listPriceUsd": 21.99,
      "priceBasis": "brand list price",
      "priceCheckedOn": "2026-10-14",
      "priceVerifiedOn": "2026-11-06",
      "amazonPriceUsd": 11.7,
      "costPer200MgUsd": 0.733,
      "certification": "USP Verified",
      "nihDsldId": null,
      "availability": "ok"
    },
    {
      "name": "Vitamin Shoppe Magnesium Glycinate 400 mg (135 tablets)",
      "brand": "The Vitamin Shoppe",
      "elementalMgPerServing": 400,
      "servingSize": "3 tablets",
      "servingsPerContainer": 45,
      "priceUsd": null,
      "listPriceUsd": null,
      "priceBasis": "no list price we could check",
      "priceCheckedOn": "2026-10-14",
      "priceVerifiedOn": "2026-11-06",
      "amazonPriceUsd": 19.99,
      "costPer200MgUsd": null,
      "certification": "None",
      "nihDsldId": null,
      "availability": "ok"
    },
    {
      "name": "KAL Magnesium Glycinate 350 mg (240 VegCaps)",
      "brand": "KAL",
      "elementalMgPerServing": 350,
      "servingSize": "4 VegCaps",
      "servingsPerContainer": 60,
      "priceUsd": null,
      "listPriceUsd": null,
      "priceBasis": "no list price we could check",
      "priceCheckedOn": "2026-10-14",
      "priceVerifiedOn": "2026-11-06",
      "amazonPriceUsd": 24.79,
      "costPer200MgUsd": null,
      "certification": "None",
      "nihDsldId": null,
      "availability": "ok"
    }
  ]
}