Mag-Ox 400 High Potency Magnesium Supplement, 120 Tablets, 2 Pack Review

Mag-Ox 400 Magnesium Mineral Dietary Supplement Tablets provide the most potent and concentrated form of magnesium available in a pure pharmaceutical grade formula. Recognized as the number one pharmacist recommended brand by U.S. News & World Report and Pharmacy Times for both 2016-2017 and 2018-2019, this unflavored supplement is specifically designed to support overall health, metabolism, and everyday vitality. Each two-pack contains a total unit count of 240 tablets, with 120 tablets per bottle, weighing 9.6 ounces and measuring 5.35 by 4.57 by 2.28 inches. The improved formula features tablets that are now coated to make them much easier to swallow. Each tablet delivers 483 mg of magnesium oxide alongside inactive ingredients including microcrystalline cellulose, croscarmellose sodium, magnesium stearate, and silicon dioxide. Furthermore, the supplement is completely sugar-free, gluten-free, and abalone-free to accommodate various dietary needs. Consistent daily magnesium intake ensures full health benefits by helping to maintain normal muscle and nerve function, supporting healthy heart rhythms, aiding in the bodily absorption of essential minerals like calcium and potassium, and supporting proper glucose metabolism. For suggested use, adults should take two tablets daily with food or as directed by a healthcare professional, and always follow the directions on the packaging. Regarding safety information, if you are pregnant or nursing, taking medication, or have kidney disease, you must consult your physician before taking this product. Users should be aware that magnesium oxide may have a laxative effect. The bottles should be kept out of reach of children, and the product should not be used if the seal under the bottle cap is broken or missing. This product is labelled to United States standards and may differ from similar products sold elsewhere in its ingredients, labeling, and allergen warnings. Statements regarding dietary supplements have not been evaluated by the Food and Drug Administration and are not intended to diagnose, treat, cure, or prevent any disease or health condition.

Product Focus: Regularity: Fast ReliefAlso graded for:Hearing and Ear RingingAlso covers:Digestion
Tier ⓘ
Members see this product's tier and why. Tiers run from 1, the strongest evidence, to 5. How we grade →
Evidence ⓘ
How strongly the evidence says this product works: human studies count most, then real reviews, then our biohacker panel.
Positive Reviews
Biohacker Mentions
Cost per month
$7

Study, Trial or Testing Result Summary

MembersHuman studies

This product provides 482.6 milligrams of magnesium as magnesium oxide per serving, which is the 800 milligrams daily dose where it typically in clinical studies, though it is the daily limit so members can choose to take . Magnesium is supported by human research for constipation. …

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Review Totals and Summary

Members3,863 reviews
3,863 reviews · Amazon 2,047 · Walmart 1,282 · Healthwarehouse 317 · Walgreens 107 · EBay 76 · Target 34

This Mag-Ox 400 Potency Magnesium Supplement has garnered attention, with approximately 3363 ratings across various stores. The vast of feedback is , with of rated reviews giving it 4 or 5 stars. …

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Biohacker Summary

MembersWhat our biohacker panel says

of the panel or uses magnesium, and sleep is the top reason, with others citing blood pressure, stress, muscle recovery, brain function and bone . Forms they favor are glycinate and threonate: four of them name threonate, with three taking 400 mg before bed, and three name glycinate, with one giving 300 mg before bed. …

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RAL Summary

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More Details

MembersBody systems · Combine with · Possible side effects

Body systems: Digestive system. Combine with and possible side are for members.

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Supplement Facts

Magnesium 482.6 mg
Supplement Facts
Serving Size 2 Tablets
Servings Per Container 60
Amount Per Serving% Daily Value
Magnesium (as Magnesium Oxide)482.6 mg

Other ingredients: Microcrystalline Cellulose, Hydroxypropyl Cellulose, Crospovidone, Hypromellose, Maltodextrin, Magnesium Stearate, Silicon Dioxide, PEG.

Directions: Take 2 tablets daily with food or as directed by a healthcare professional.

Label source: Ebay · Report a label change

Where to Buy

Mag-Ox · Amazon · Walmart
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More regularity: fast relief products

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Graded October 28, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.