MgO 400 mg®

Objective insights generated automatically from the official DSLD label — a quick, factual read of how this product is formulated and disclosed.

This analysis is generated algorithmically from label data for educational reference only. It is not a product endorsement, ranking, or medical advice.

Allergen flags are parsed automatically from the official label's claims and statements. Always verify against the physical product label before use, especially if you have a severe allergy.

Serving Size: 1 Tablet(s) · 1 per day

Not Present

• 

  21st Century Magnesium Oxide 400 Mg Tablets

  iHerb4.8(271)

  $7.49
• 

  21st Century MgO 400 mg Tablets - 90 ct Pack of 3

  GoSupps.com4.8(271)

  $64.99
• 

  21st Century Magnesium Tablets

  iHerb4.7(24000)

  $7.99
• 

  21st Century Cal Mag Zinc + D3 Tablets

  Swanson Health Products4.8(5600)

  $5.49Lowest
• 

  21st Century Folic Acid

  Hargraves Online Healthcare4.8(6600)

  $5.99
• 

  21st Century E-400 Softgels

  Target4.7(4900)

  $19.99
• 

  Manuka Health Honey MGO Manuka

  Manuka Health4.8(2200)

  $43.99
• 

  Co Q-10 400 mg 21st Century 30 Capsules

  iHerb5.0(38)

  $22.49

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• The Vitamin Shoppe

  4.3 (184)

  Vitamin & supplements store

  12 4th Ave, Brooklyn, NY 11217, United States

  Directions+1 718-858-8314

• GNC

  4.2 (280)

  Vitamin & supplements store

  134-136 Fulton St, New York, NY 10038, United States

  Directions+1 212-374-9473

• GNC

  4.4 (92)

  Vitamin & supplements store

  753 Broadway Spc 753, New York, NY 10003, United States

  Directions+1 212-380-5999

• GNC

  4.7 (202)

  Vitamin & supplements store

  2 Pennsylvania Plaza Ste 29B, New York, NY 10121, United States

  Directions+1 212-239-1251

• The Vitamin Shoppe

  4.5 (62)

  Vitamin & supplements store

  480 86th St, Brooklyn, NY 11209, United States

  Directions+1 718-491-9768

• GNC

  4.3 (104)

  Vitamin & supplements store

  32 Graham Ave, Brooklyn, NY 11206, United States

  Directions+1 718-599-2887

• GNC

  3.7 (106)

  Vitamin & supplements store

  2 Broadway, New York, NY 10004, United States

  Directions+1 212-514-5770

• GNC

  3.6 (151)

  Vitamin & supplements store

  549 6th Ave, New York, NY 10011, United States

  Directions+1 212-924-5925

• Magnesium: Health Effects, Deficiency Burden, and Future Public Health Directions

  MM Sarić, T Sorić, ŽJ Kasap, NL Šikić, M Mavar… - Nutrients, 2025 - pmc.ncbi.nlm.nih.gov

  … of healthy periadolescent girls, 300 mg/day magnesium oxide … RCTs of magnesium supplementation in otherwise healthy … magnesium oxide (500 mg/day) and zinc gluconate (50 …

  202521 citations

• An update on magnesium and bone health

  M Rondanelli, MA Faliva, A Tartara, C Gasparri… - Biometals, 2021 - Springer

  … intake and seven studies concern Mg supplementation, alone or in combination with other nutrients. From the various studies carried out on the serum concentration of …

  2021268 citations

• Effect of magnesium supplementation on depression status in depressed patients with magnesium deficiency: A randomized, double-blind, placebo-controlled trial

  A Rajizadeh, H Mozaffari-Khosravi, M Yassini-Ardakani… - Nutrition, 2017 - Elsevier

  … MG received two 250-mg magnesium oxide tablets on a daily basis (21st Century® Healthcare… The findings of this study indicated that daily consumption of 500 mg magnesium oxide for …

  2017143 citations

• The effects of magnesium and vitamin E co-supplementation on hormonal status and biomarkers of inflammation and oxidative stress in women with polycystic …

  M Shokrpour, Z Asemi - Biological trace element research, 2018 - academia.edu

  … 250 mg/ day magnesium oxide (Twenty First Century Pharmaceutical Company, AZ, USA) plus 400 IU/… reminders to take the supplements. Patients were requested to have their regular …

  201866 citations

• Magnesium: novel applications in cardiovascular disease–a review of the literature

  EA Kupetsky-Rincon, J Uitto - Annals of Nutrition and Metabolism, 2012 - karger.com

  … , in the 17th century, it has multiple uses in the medical field, espe… treatment group (n = 30) given magnesium oxide 400 mg … BPs in the magnesium oxide supplementation period vs. in …

  201299 citations

• Oral magnesium supplementation improved lipid profile but increased insulin resistance in patients with diabetic nephropathy: a double-blind randomized controlled …

  M Sadeghian, L Azadbakht, N Khalili… - … Trace Element Research, 2020 - Springer

  … with healthy subjects. Some studies have shown that magnesium supplementation might … Findings from our study revealed that supplementation with 250 mg MgO had no significant …

  202039 citations

• Magnesium Forms Explained: Oxide, Citrate, and Glycinate

  The magnesium form on a label affects how much elemental magnesium you get. Here is how the common forms compare.

  VitaSuppTrack Editorial· Jun 24, 2026

Data sourced from the U.S. National Institutes of Health, Office of Dietary Supplements Dietary Supplement Label Database (DSLD) · Label entered 2019-09-24. DSLD Label ID: 206639. This information is provided for educational reference only and is not medical advice. Always follow the product label and consult a doctor or pharmacist before use.