21st Century Magnesium Review
Magnesium is an essential mineral and supports bone and muscle health. For over 30 years, 21ST Century Vitamins has provided trusted vitamins and supplements by upholding the highest standards of quality in every product we offer. From sourcing the finest ingredients to rigorous testing and production processes, we ensure that every product meets our stringent quality benchmarks. We are here to support your wellness every step of the way. Directions: As a mineral supplement, adults take one (1) tablet daily with any meal or as directed by a healthcare provider. Do not exceed recommended dosage. Individual results may vary. Warning: Consult a healthcare provider prior to use if pregnant, nursing, on medications, have a medical condition, including kidney disease, or are planning a medical procedure. Stop use and contact a physician if adverse reactions occur. Keep out of reach of children. Do not use if product appears to be tampered with or seal is broken. Store at room temperature. Supplement Facts: Serving Size 1 Tablet. Elemental Magnesium (as Magnesium Oxide) 250 mg, 60% Daily Value. Calcium (as Calcium Carbonate) 65 mg, 5% Daily Value. No added Sugar, Yeast, Preservatives, Artificial Flavors or Colors. Dietary restrictions: Gluten Free, Non-GMO, Vegetarian, Vegan. Product is offered in 110 Tablets and 250 Tablets sizes.
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Supplement Facts
Calcium 65 mg · Magnesium 250 mg
| Calcium (as Calcium Carbonate) | 65 mg | 5% |
| Magnesium (as Magnesium Oxide) | 250 mg | 60% |
Other ingredients: Cellulose, Stearic Acid, Croscarmellose Sodium, Kelp. Contains <2% of: Gum Acacia, Magnesium Silicate, Magnesium Stearate, Silicon Dioxide.
Directions: Directions: As a mineral supplement, adults take one (1) tablet daily with any meal or as directed by a healthcare provider. Do not exceed recommended dosage. Individual results may vary.
Label source: 21stcenturyvitamins · Report a label change
Where to Buy
21st Century · iHerb · Healthwarehouse
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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.

