Protocol
Magnesium Glycinate 300–400 mg
No randomized trial of magnesium glycinate has measured insulin resistance; the class evidence for other magnesium salts is mixed.
Grade D, not yet tested: no human randomized trial has been run. This D records missing trials, not a finding that it does not work. How to read a grade →
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How this letter has changedLatest: October 2026 · Corrected.
The description said magnesium improved insulin resistance in humans on the strength of Morais et al. (Nutrition, 2017; PMID PubMed ID: the permanent number the US National Library of Medicine gives a published paper. Each one links to that paper's record on PubMed. 28526383), a narrative review of 12 trials of other salts whose own conclusion limits benefit to magnesium-deficient, insulin-resistant people. Added: Amiri et al. (BMC Nutr, 2026; PMID 42426860), 15 trials in diabetes and prediabetes, no significant change in insulin or HOMA-IR; Simental-Mendia et al. (Pharmacol Res, 2016; PMID 27329332) and Mohammadi et al. (Nutrients, 2026; PMID 42588058), modest HOMA-IR reductions. The glycinate form remains untested on this endpoint The outcome a trial measures to decide whether the treatment worked, such as heart attacks, blood pressure or a symptom score., so D Route 1 stands; the reading now says the class evidence would be C, not B. Applied the written grade definition under the editor's standing instruction of October 2026 (Arnold Sandlow, D.C.).PMID 27329332 PMID 28526383 PMID 42426860 PMID 42588058
The magnesium glycinate 300 to 400 mg protocol held a B on a review of trials that used other magnesium salts (Morais et al., Nutrition 2017; PMID 28526383). EBL grades magnesium by the salt on the label. No randomized trial of magnesium glycinate alone has measured insulin resistance, and a 2024 clamp trial of oral magnesium was null (Drenthen et al., Diabetologia 2024; PMID 37922013). Untested for this salt: D on Route 1. This is not a finding that magnesium does not work. Editor adjudication, October 2026.PMID 28526383 PMID 37922013
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This protocol is magnesium glycinate at 300 to 400 mg a day for blood sugar control. No study of magnesium glycinate has measured how well the body uses insulin. Studies of other forms of magnesium gave mixed results, with benefit mainly in people who were low in magnesium to begin with. So this form, for this use, is untested.
No randomized trial of magnesium glycinate has measured insulin resistance; the class evidence for other magnesium salts is mixed. A narrative systematic review A review that searches for every study on a question using a method set in advance, then assesses them together. of 12 trials found benefit mainly in people who were both magnesium-deficient and insulin-resistant (Morais 2017; PMID 28526383). A 2026 meta-analysis of 15 trials in diabetes and prediabetes found no significant change in insulin or HOMA-IR (Amiri 2026; PMID 42426860), a 2024 crossover A trial design in which each participant receives both the treatment and the comparison, one after the other, and serves as their own control. trial found no change in clamp-measured insulin sensitivity (Drenthen 2024; PMID 37922013), while a 2016 pooling found HOMA-IR lower (Simental-Mendia 2016; PMID 27329332) and a 2026 dose-response pooling of 78 trials a modest HOMA-IR reduction of uncertain clinical relevance (Mohammadi 2026; PMID 42588058).
Why this gradeGrade D, not yet tested. The reasoning, and what the grade does not cover.
Grade D on Route 1 for insulin resistance: no randomized trial of magnesium glycinate has measured insulin resistance, and the PubMed search recorded on this record (October 2026) found none. The class evidence for other magnesium salts is mixed: a narrative review found benefit mainly in magnesium-deficient, insulin-resistant people (Morais et al., 2017; PMID 28526383), one pooling found HOMA-IR lower (Simental-Mendia et al., 2016; PMID 27329332) and another a modest reduction of uncertain relevance (Mohammadi et al., 2026; PMID 42588058), while the 2026 meta-analysis of 15 trials in diabetes and prediabetes found no significant change in insulin or HOMA-IR (Amiri et al., 2026; PMID 42426860) and a crossover trial found no change in clamp-measured insulin sensitivity (Drenthen et al., 2024; PMID 37922013). Were the record graded on magnesium as a class it would be C on that mixed evidence, not the B it once carried.
WHAT THIS GRADE DOES NOT COVERmagnesium deficiency, other magnesium salts, blood pressure, sleep, or any other endpoint, and people with low magnesium in particular. The D records an untested form, not a failed trial.
A grade describes the human evidence for a named use. It is not advice, and it is not a judgment on any individual prescription. How the letters are decided →
The evidence, in fullFive papers, each linked to its PubMed record.
Morais et al. (Nutrition, 2017; PMID 28526383): narrative systematic review of 12 trials of magnesium supplementation and insulin resistance, no pooled estimate; the trials used other magnesium salts (chloride, aspartate), not glycinate, and benefit was concentrated in people with low magnesium and insulin resistance. Amiri et al. (BMC Nutr, 2026; PMID 42426860): meta-analysis of 15 randomized trials, 1,085 people with diabetes or prediabetes; insulin (MD -1.73, 95% CI -3.73 to 0.27) and HOMA-IR (MD -0.74, 95% CI -1.58 to 0.09) not significantly changed. Drenthen et al. (Diabetologia, 2024; PMID 37922013): randomized crossover; oral magnesium did not change clamp-measured insulin sensitivity in type 2 diabetes with low magnesium. Simental-Mendia et al. (Pharmacol Res, 2016; PMID 27329332): meta-analysis; HOMA-IR lower (WMD -0.67), glucose and HbA1c A blood test that reflects average blood sugar over the previous two to three months. unchanged. Mohammadi et al. (Nutrients, 2026; PMID 42588058): dose-response meta-analysis of 78 trials; HOMA-IR 0.48 lower, with the authors noting uncertain clinical relevance. No randomized trial of magnesium glycinate has measured insulin resistance.
Serum magnesium at baseline and 8 weeks, targeting the upper half of the normal range. For the primary indication (sleep, muscle cramps, or blood pressure), use the relevant validated scale or measure at baseline and 6 weeks. Glycinate form is chosen for tolerability: if GI symptoms occur, split the dose across two meals.
Evidence notes:
Endpoint graded: Insulin resistance (surrogate)
Last reviewed: July 2026
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