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#14 in Minerals Third-Party Tested

Nature Made Magnesium Oxide 400mg (150 Softgels)

by Nature Made

"USP-verified magnesium at $0.07/day — America's most trusted supplement brand"

Amazon Rating
4.7/5
Reviews
42,600+
Price Range
$8-12
Servings
150 servings
USP VerifiedNon-GMO
Our Editorial Rating
8.2
Very Good
FormSoftgel
CategoryMinerals
SubcategoryMagnesium Oxide (Budget, General Use)
View on Amazon

Overview

Nature Made Magnesium Oxide 400mg is one of the best-selling magnesium supplements in America, backed by USP verification and 42,600+ reviews. While magnesium oxide has lower bioavailability than glycinate or citrate forms, it provides the highest elemental magnesium per capsule (400mg = 95% DV) at the lowest cost. The USP verification ensures potency, purity, and proper dissolution.

Key Ingredients

IngredientAmount
Magnesium (as Magnesium Oxide)400 mg (95% DV)

Pros & Cons

What We Like

  • USP Verified quality assurance
  • 42,600+ reviews, 4.7 stars
  • 150 softgels = 5-month supply
  • $0.07/day — unbeatable value
  • 400mg elemental magnesium per softgel

What Could Be Better

  • Oxide form has lower bioavailability (~4%)
  • May cause loose stools
  • Not ideal for sleep or anxiety
  • Less absorbed than glycinate/citrate

Who Is This For?

Best For

  • Budget magnesium supplementation
  • General magnesium deficiency
  • Those wanting USP verification
  • Value-first shoppers

Not Ideal For

  • Those seeking sleep/relaxation benefits
  • GI-sensitive individuals
  • Those wanting high bioavailability

Our Verdict

8.2/10 — Very Good

The value king of magnesium. While oxide isn't the most bioavailable form, USP verification at $0.07/day makes this the rational choice for basic magnesium supplementation.

Alternatives to Consider

No direct alternatives listed for this product yet.