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Strong EvidenceEssentialssupplements

Magnesium (Glycinate / Threonate)

Essential mineral for 300+ enzymatic reactions including sleep and nerve function

What It Is

Magnesium is involved in over 300 enzymatic reactions and most adults are deficient. Glycinate form is gentle and well-absorbed; threonate (Magtein) crosses the blood-brain barrier for cognitive support.

How It Works

Magnesium is a cofactor for ATP synthesis (Mg-ATP is the biologically active form), DNA repair enzymes, and GABA receptor activation (promoting sleep). Threonate specifically increases brain magnesium levels.

The Science

Suboptimal magnesium status in the United States: are the health consequences underestimated?

Nutrition Reviews (2012) · PubMed

Review establishing widespread magnesium inadequacy and its association with chronic disease.

Enhancement of learning and memory by elevating brain magnesium

Neuron (2010) · PubMed

Magnesium threonate increased brain magnesium and improved learning/memory in animal models (foundational study for Magtein).

Dosage

200–400mg elemental magnesium daily. Glycinate for general use and sleep; threonate (2g Magtein) for cognitive focus. Can combine forms.

Safety

Very safe. Excess is excreted renally in healthy individuals. High doses of some forms (oxide, citrate) cause loose stools. Avoid in severe renal impairment.

Skeptic's Corner

Magnesium supplementation is most beneficial for those who are deficient — which is admittedly common (~50% of US adults). For those with adequate dietary intake, supplementation may offer diminishing returns. The cognitive claims for threonate are based on limited human data.

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