You're getting 500mg of **Magnesium** per capsule — well above the 100–400mg clinical supplemental range — from a blend of oxide, citrate, and succinate. That's a generous dose on paper, but the oxide portion absorbs poorly (roughly 4%), so the effective amount reaching your body is significantly lower than the label number suggests. The citrate fraction absorbs well and contributes meaningfully to the dose.

**Magnesium** is involved in hundreds of body processes — energy production, muscle and nerve function, heart rhythm, and sleep quality. Deficiency is extremely common, estimated to affect over half the population, so supplementing makes sense for most people. At this dose level, you're well-covered across the health areas magnesium supports, from stress and mood to bone and heart health.

The 500mg per-capsule dose exceeds the 350mg tolerable upper limit for supplemental magnesium, which means GI side effects like loose stools are possible — especially from the oxide component. If you experience digestive discomfort, splitting to half a capsule or switching to a single well-absorbed form like glycinate or citrate would be worth considering.

BioStacks
Life Extension

Magnesium Caps, 500 mg, 100 Vegetarian Capsules

1 Capsule · 100 servings · $0.09/serving

iHerbAmazon

Best for

Heart

Ingredients (1)

Magnesium

100%

Dose

500 mg

Target

100–400 mg

Form

Standard

Other Ingredients (4)

Silicon DioxideAnti-caking

Fine silica powder used to prevent clumping

Microcrystalline CelluloseBinder

Plant-derived cellulose used as a binder and filler in supplements

Stearic AcidLubricant

Saturated fatty acid used as tablet lubricant

Microcrystalline CelluloseBinder

Plant-derived cellulose used as a binder and filler in supplements

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Sources & Scoring

Nutrient data (RDA, UL, and safety thresholds) sourced from: NIH Office of Dietary Supplements and National Academies Dietary Reference Intakes (DRI).

This is not medical advice. Consult a healthcare provider before making changes to your supplement routine.

The score analyzes what's on the label: ingredient doses vs. clinical ranges, chemical forms, evidence levels, and known interactions. It does not verify label accuracy or test for contaminants — for that, look for third-party certifications like USP or NSF.

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