Magnesium

Magnesium · an essential mineral sold for blood pressure, sleep, cramps and calm

SUPPLEMENTFACTSTACK.COM™
Consumer Brief · October 2026
15 October 2026 · v3

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Claim Verdict

Promising

Blood Pressure on Medication, Migraine

Research Confidence

Low

Blood Pressure on Medication

Supporting Evidence

Promising

Blood Pressure on Medication

Safety Risk

Caution

Blood Pressure on Medication

Product Quality

Inconsistent

Blood Pressure on Medication

Bottom line: Magnesium may help blood pressure in people on BP drugs, and migraine, but most claims are unproven. Keep to 250 mg elemental a day, and skip it for cramps.

What’s New This Month

Cramps: The Cochrane review’s own abstract shows leg cramps changed by 0.18 fewer a week, with a range from 0.84 fewer to 0.49 more, so the result may be zero. Cramps stay Unsupported. ¹
Sleep: The newest review of 12 trials says current evidence does not support magnesium as a routine treatment for insomnia. The 2024 correction to the main sleep review changes wording and study counts, not its results. ² ³
More recalls found: Health Canada lists six magnesium supplement recalls in the past two years, up from three, for undeclared magnesium oxide, defective tamper seals, wrong label details and capsule residue. The FDA gummy recall for undeclared melatonin is still ongoing. ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ ¹⁰
FDA records: FDA adverse-event reports (not proof of cause) name magnesium products, including laxative overdoses. An FDA import alert lists a magnesium-labelled product for an undeclared colour; it is not a recall of shelf product. ¹¹ ¹²

Overview

Magnesium is a mineral your body needs. Supplements sell it as salts such as glycinate, citrate, malate, oxide and threonate.

About 48% of Americans get less than the average need from food, but that is not the same as a deficiency. ¹³

Labels claim better sleep, calm, fewer cramps, heart health, memory, energy and more.

How We Researched It

We rate each marketing claim with a modified version of GRADE, the system medical researchers use to say how sure we can be (i.e., high, moderate, low or very low), and check each trial with the Cochrane risk-of-bias tool, which asks whether a study’s design could skew its results. For magnesium we screened about 70 records and used 30 evidence rows, mostly from 2022 to 2026. We also checked 10 regulators and safety databases, including the FDA, Health Canada, EFSA and NIH.

Research NotesTop three benefits

Blood Pressure on Medication GRADE: Low

A 2025 review of 38 trials (2,709 people) found top blood pressure fell 7.7 mmHg in people on BP drugs and 6.0 in people low in magnesium. Groups with normal pressure saw no change. ¹⁶

Bias check: This rests on one review; the subgroup ranges were not pulled, results varied widely, and higher doses did not work better.

Migraine GRADE: Low

NIH relays a 2012 neurology guideline that rated magnesium “probably effective” for migraine, at doses above the supplement upper limit. ¹³

Bias check: We read no migraine trial directly, and the Cochrane migraine review is still only a plan.

Sleep GRADE: Low

In a 155-person trial, 250 mg of bisglycinate for 4 weeks eased insomnia scores slightly (effect size 0.2, p=0.049). An older review of 3 small trials found people fell asleep 17 minutes faster. ¹⁷ ²³

Bias check: The newest review of 12 trials found no pooled effect, and a threonate trial found no change on a sleep tracker. ² ¹⁸

Benefit Evaluation

Claim	Claim Verdict	Research Confidence	Supporting Evidence	Safety Risk	Product Quality	FactStack™ Rating
Blood Pressure on Medication	Promising	Low	Promising	Caution	Inconsistent	Caution
Migraine	Promising	Low	Promising	Caution	Inconsistent	Caution
Sleep	TBD	Low	TBD	Caution	Inconsistent	Warning
Stress	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Anxiety	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Mood	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Heart Rate and Rhythm	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Inflammation and Lipids	TBD	Low	TBD	Caution	Inconsistent	Warning
Bone Health	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Memory	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Recovery	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Constipation and PMS	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Lung and Airway Relaxation	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Energy and Immunity	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Disease Treatment	TBD	Very Low	TBD	Caution	Inconsistent	Warning
Blood Pressure	Doubtful	Low	Doubtful	Caution	Inconsistent	Warning
Blood Sugar	Doubtful	Low	Doubtful	Caution	Inconsistent	Warning
Muscle Cramps	Unsupported	Moderate	Unconvincing	Caution	Inconsistent	Warning

What Sellers Say vs. What Studies Show

“Stops muscle cramps.”	A Cochrane review found no meaningful drop in cramps at four weeks. In a 2026 trial, magnesium did nothing while knee-high stockings did. ¹ ¹⁴
“Lowers blood pressure for everyone.”	Pooled trials found about a 2.5 point drop, below our bar. Larger drops came only in people on BP drugs or low in magnesium. ¹⁵ ¹⁶
“Proven to help you sleep.”	The best trial found a small gain. The newest review of 12 trials found no pooled effect. ¹⁷ ²
“Glycinate is gentle on the stomach.”	No head-to-head trial shows it. Stomach upset hit 11% to 37% of people across magnesium groups in the Cochrane review. ¹
“Threonate gets into your brain.”	The trials measured sleep and thinking tests, not brain magnesium. We found no human test showing brain levels rise. ¹⁸
“The label tells you what’s inside.”	Two Canadian bisglycinate products held undeclared magnesium oxide, and a third brand’s capsules had defective tamper seals. ⁴ ⁵ ⁹

Trial ParametersIf you try it

Who	Adults with normal kidneys, low intake and no interacting drug. Evidence leans positive only for blood pressure on BP drugs and migraine.
Dose	At or below 250 mg of elemental magnesium a day from supplements. Stop if diarrhea develops.
Ceiling	NIH ODS upper limit: 350 mg a day from supplements. EFSA lists 250 mg a day (a 2001 SCF value).
Duration	Trials ran 4 to 12 weeks. For cramps, judge the effect at eight weeks.
Form	A label stating elemental magnesium, with a current certificate of analysis. Avoid recalled lots, including gummies with undeclared melatonin.
Ask First	Kidney impairment; pregnancy, breastfeeding or children (not evaluated); bisphosphonates, tetracyclines or quinolones; diuretics; acid reducers (PPIs); migraine, depression or bone loss use.

Source: ¹³ ¹⁹ and studies cited.

How to Take It

Pick a plan	Take no more than 250 mg of elemental magnesium a day, for a 4 to 12 week trial. Count the elemental amount, not the salt’s weight.
Time of day	Not reported.
With food	Not reported.
What to expect	Blood pressure changes took about 12 weeks in the trials. Loose stools can start at once. For cramps, judge it at 8 weeks, not 4. ¹⁶ ¹³
How to take	Capsules or powder. Take bone drugs (bisphosphonates) apart from magnesium. Take tetracycline or quinolone antibiotics 2 hours before it or 4 to 6 hours after. ¹³

Works With / Don’t Mix With

✓ Works with

Blood-pressure care you already have. The biggest drops came in people already on blood-pressure drugs. It adds to care; it does not replace it. ¹⁶

For leg cramps, compression stockings. In a 2026 trial, knee-high stockings cut cramps by about 1.4 a week while magnesium did nothing. ¹⁴

Not reported: we found no supplement shown to add to its effect.

⚠ Ask first / don’t mix

Kidney problems. Magnesium can build up to toxic levels when the kidneys clear it poorly. Use it only under a doctor’s care. ¹³

Bone drugs (bisphosphonates). Take them apart from magnesium. ¹³

Tetracycline or quinolone antibiotics. Take the antibiotic 2 hours before or 4 to 6 hours after magnesium. ¹³

Water pills (diuretics) and long-term acid reducers (PPIs). They can lower your magnesium level; ask first. ¹³

Magnesium gummies sold for sleep. A recalled gummy held undeclared melatonin, a sleep hormone, which can add to the effect of sleep aids, allergy pills or alcohol. ¹⁰

Pregnant, breastfeeding or buying for a child? We did not evaluate these groups, so ask first. The pregnancy cramp trials in the Cochrane review were at high risk of bias. ¹ Not reported: combinations with other supplements tested in people.

Manufacturer Recalls & WarningsLast 36 months, newest first

Date	Maker / Brand	Product	Action	Src
Jul 2026	Guangdong Come Health Biotechnology Co., Ltd. (China)	Cutting Mix-Magnesium + Yerba Support	FDA import alert 45-02: undeclared and non-permitted colour (Ponceau 4R). It means detention at the border, not a recall of shelf product.	¹²
Jun 2026	Dkiru LLC (Adndale)	Adndale Magnesium Glycinate Gummies 400 mg, 90 count	FDA Class II recall H-1079-2026, started 12 May 2026, 13,920 bottles: undeclared melatonin (a sleep hormone). Still ongoing. The record does not state the melatonin amount.	¹⁰
May 2026	Meta Labs Pharmaceuticals, LLC	Magnesium-labelled products	FDA warning letter (CMS 725130) to a firm making magnesium claims.	²⁰
Apr 2026	Jamieson Laboratories	Jamieson magnesium bisglycinate capsules (NPN 80131651)	Health Canada Type III recall RA-81822: tamper-evident seals may be defective.	⁹
Jan 2026	Raw Elements Inc. (BiOptimizers)	Magnesium Breakthrough capsules, lot 2504909	Health Canada Type III recall RA-81499: small amounts of residue on some capsules.	⁸
Nov 2025	Nutralab Corp Canada (MapleLife)	MapleLife Magnesium Bisglycinate 200 mg, lot MLMG252	Health Canada Type III recall RA-81280: undeclared magnesium oxide.	⁵
Nov 2025	Shoppers Drug Mart/Loblaw (Life Brand); made for them by Nutralab	Life Brand Magnesium Bisglycinate 200 mg, all lots since July 2023	Health Canada Type III recall RA-78492: undeclared magnesium oxide.	⁴
Sep 2025	ITL Health	MAG Trio capsules, lots 424 and 436	Health Canada Type III recall RA-78116: incorrect NPN on the label; magnesium levels may be outside the labelled claim.	⁷
Jun 2025	Nutralab Canada	Dr. Nutrition 360 Magnesium 200 mg capsules, lot DNMC247	Health Canada Type III recall RA-77657: incorrect non-medicinal ingredient (gelatin) on the label.	⁶
Mar 2025	Mother Earth Minerals, Inc.	Magnesium-labelled products	FDA warning letter (CMS 692527) to a firm making magnesium claims.	²⁰
Oct 2023	Metagenics (Aust) Pty Ltd (Ethical Nutrients)	Ethical Nutrients Mega Magnesium Raspberry Powder, batch 007764	Australia TGA recall: vitamin B6 twice the labelled amount. Older than two years.	²¹

We found one FDA recall of a magnesium supplement in the past two years, and it is still open. ²² ¹⁰ Health Canada lists six magnesium supplement recalls in that time. ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ We found no other FDA import alert naming magnesium in the past two years. ¹² FDA has issued warning letters to firms making magnesium claims. ²⁰ FDA adverse-event reports (not proof of cause) name magnesium products, including laxative overdoses. ¹¹

Where to Buy

We compare products side-by-side not just on price, but on whether NSF lists the product as NSF/ANSI 173 Contents Certified (an independent lab confirms the label matches the contents), whether it is NSF Certified for Sport, whether USP lists it as USP Verified, and whether the seller says it is manufactured in the USA. We leave out a brand’s products for this supplement when, in the last 36 months, the FDA took action against that brand over this supplement (a Class I or II recall, a warning letter, an import alert or an advisory letter). We also leave out any brand with an FDA Class II recall or warning letter on any product. We also leave out any product named in a California Prop 65 notice or a non-US recall, along with that brand’s products of the same ingredient and form. Brands with other actions stay listed and are marked in the Recall Screen column. Our goal remains to provide you, the Consumer, with the information and data necessary to make an informed purchasing decision. Prices reflected below are static and subject to change.

Ratings above describe the ingredient’s research, not any product listed below.

#	Retailer	Product	Price	NSF 173	NSF Sport	Mfg. in USA (per seller)	Recall Screen	Affiliate link
1	Amazon	Klean Athlete Klean Magnesium, 90 Capsules	Check Price	✓	✓	✓	✓*	View on Amazon ↗
2	iHerb	Codeage, Liposomal Magnesium Glycinate, 120 Vegetable Capsules	$29.99	✓	✓	✓	✓*	View on iHerb ↗
3	iHerb	Designs For Health, Designs For Sport®, Magnesium Bisglycinate, 120 Vegetarian Capsules (150 mg per Capsule)	$40.74	✓	✓	✓	✓*	View on iHerb ↗
4	Amazon	THORNE Magnesium Glycinate, 90 Capsules	Check Price	✓		✓	✓*	View on Amazon ↗
5	Green's Nutrition	Nutricost Magnesium Citrate 60 Caps	$9.99			✓	✓*	View on Green's Nutrition ↗
6	Green's Nutrition	Solaray Magnesium Asporotate 60 Caps	$10.59			✓	✓*	View on Green's Nutrition ↗
7	HerbsPro	Now Foods, Magnesium Citrate, 200 mg, 100 Tabs	$12.49			✓	✓*	View on HerbsPro ↗
8	Green's Nutrition	Nutricost Magnesium Glycinate Capsules 180 Count	$23.95			✓	✓*	View on Green's Nutrition ↗
9	Green's Nutrition	Solaray Magnesium Citrate 180 Veg Caps	$26.09			✓	✓*	View on Green's Nutrition ↗
10	Green's Nutrition	NOW Foods Magnesium Glycinate 180 Tabs	$31.99			✓	✓*	View on Green's Nutrition ↗

Per NSF and USP public listings, as of our 15 October 2026 product review; blank = not found.

Every retailer in this table is an affiliate partner, and we earn a commission on every product listed. Our affiliate partners across the site are Amazon, Botanic Choice, Everlywell, Green’s Nutrition, HerbsPro and iHerb. As an Amazon Associate I earn from qualifying purchases. Our evidence ratings are set before any products are added. No brand or retailer pays to be rated or reviews our content before it is published. Always confirm certifications on the provider’s website before you buy.

Recall Screen: ✓* means the brand’s only actions in the last 36 months are a California Prop 65 notice, a non-US recall or sales action, an FDA Class III supplement recall, or a food recall, each on a different product from the one listed. Prop 65 notices are allegations by private enforcers, not findings. A blank means the brand had another FDA action in that period, such as an import alert or a recall of a different product, or a minor (Class III) recall of this product.

Sources

1. Garrison et al. Magnesium for skeletal muscle cramps: Cochrane systematic review (CD009402). Cochrane Database of Systematic Reviews, 2020. pubmed.ncbi.nlm.nih.gov/32956536/

2. Lopresti, Smith and Drummond. Magnesium supplementation for sleep in adults: systematic review of randomized controlled trials. Journal of Dietary Supplements, 2026. doi.org/10.1080/19390211.2026.2719670

3. Correction to Mah and Pitre, Oral magnesium supplementation for insomnia in older adults: meta-analysis. BMC Complementary Medicine and Therapies, 19 Dec 2024. doi.org/10.1186/s12906-024-04721-w

4. Health product recall RA-78492: Life Brand Magnesium Bisglycinate 200mg, undeclared ingredient (magnesium oxide). Health Canada, 12 Nov 2025. recalls-rappels.canada.ca/en/alert-recall/life-brand-magnesium-bisglycinate-200mg-undeclared-ingredient-magnesium-oxide

5. Health product recall RA-81280: MapleLife Magnesium Bisglycinate 200mg, undeclared ingredient (magnesium oxide). Health Canada, 26 Nov 2025. recalls-rappels.canada.ca/en/alert-recall/maplelife-magnesium-bisglycinate-200mg-undeclared-ingredient-magnesium-oxide

6. Health product recall RA-77657: Dr. Nutrition 360 Magnesium 200 mg capsules, incorrect non-medicinal ingredient. Health Canada, 30 Jun 2025. recalls-rappels.canada.ca/en

7. Health product recall RA-78116: MAG Trio capsules, incorrect NPN and may contain magnesium levels outside labelled claim. Health Canada, 23 Sep 2025. recalls-rappels.canada.ca/en/alert-recall/mag-trio-capsules-incorrect-npn-may-contain-magnesium-levels-outside-labelled-claim

8. Health product recall RA-81499: BiOptimizers Magnesium Breakthrough capsules, residue on capsules. Health Canada, 19 Jan 2026. recalls-rappels.canada.ca/en/alert-recall/bioptimizers-magnesium-breakthrough-capsules-residue-capsules

9. Health product recall RA-81822: Jamieson Laboratories products, tamper-evident seals defective. Health Canada, 1 Apr 2026. recalls-rappels.canada.ca/en/alert-recall/jamieson-laboratories-products-recall-tamper-evident-seals-defective

10. Recall H-1079-2026, Dkiru LLC Adndale Magnesium Glycinate Gummies 400 mg (Class II; ongoing). US Food and Drug Administration (openFDA food enforcement), 24 Jun 2026. api.fda.gov/food/enforcement.json?search=recall_number.exact:%22H-1079-2026%22

11. CAERS adverse-event reports with magnesium in a product name (openFDA food event records). US Food and Drug Administration (openFDA), 6 Oct 2026. api.fda.gov/food/event.json?search=products.name_brand:magnesium

12. Import Alert 45-02 (importalert_118). US Food and Drug Administration, 31 Jul 2026 (page re-read 6 Oct 2026). www.accessdata.fda.gov/cms_ia/importalert_118.html

13. Magnesium: Health Professional Fact Sheet. NIH Office of Dietary Supplements, 6 Jan 2026. ods.od.nih.gov/factsheets/Magnesium-HealthProfessional/

14. Kuusipalo et al. Magnesium or compression stockings for leg cramps in adults 50 to 85: three-arm randomized trial. Trials, 2026. doi.org/10.1186/s13063-025-09370-z

15. Mohammadi et al. Magnesium supplementation and cardiometabolic risk factors: dose-response meta-analysis of 78 randomized trials. Nutrients, 2026. doi.org/10.3390/nu18152435

16. Argeros et al. Magnesium supplementation and blood pressure: meta-analysis of 38 randomized trials. Hypertension, 2025. doi.org/10.1161/HYPERTENSIONAHA.125.25129

17. Schuster et al. Magnesium bisglycinate 250 mg and insomnia in adults with poor sleep: randomized trial. Nature and Science of Sleep, 2025. doi.org/10.2147/NSS.S524348

18. Lopresti and Smith. Magnesium L-threonate (Magtein) for cognition and sleep: randomized trial. Frontiers in Nutrition, 2026. doi.org/10.3389/fnut.2025.1729164

19. Overview on Tolerable Upper Intake Levels as derived by the Scientific Committee on Food (SCF) and the EFSA Panel. European Food Safety Authority, Aug 2025. www.efsa.europa.eu/sites/default/files/2024-05/ul-summary-report.pdf

20. Warning Letters table, filtered for magnesium (Meta Labs Pharmaceuticals, CMS 725130; Mother Earth Minerals, CMS 692527). US Food and Drug Administration, 6 Oct 2026. www.fda.gov/inspections-compliance-enforcement-and-criminal-investigations/compliance-actions-and-activities/warning-letters

21. Recall: Ethical Nutrients Mega Magnesium Raspberry Powder, batch 007764. Australian Therapeutic Goods Administration (TGA), 17 Oct 2023. www.tga.gov.au/safety/recalls

22. openFDA food enforcement records, search for magnesium. US Food and Drug Administration (openFDA), 6 Oct 2026. api.fda.gov/food/enforcement.json?search=product_description:magnesium

23. Mah and Pitre. Oral magnesium supplementation for insomnia in older adults: meta-analysis of 3 randomized trials. BMC Complementary Medicine and Therapies, 2021. doi.org/10.1186/s12906-021-03297-z

Disclaimer. This brief is for general education only and is not medical advice, diagnosis or treatment. Talk with your doctor or pharmacist before starting any supplement, especially if you take medication, have a health condition, or are planning surgery. These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Research summaries reflect sources available on the date shown and may change. FactStack™ Research, LLC does not make, sell or warrant any product named here and is not responsible for how any product is made, sold or used.

Magnesium · SupplementFactStack.com™ Consumer Brief · October 2026