Iron Bisglycinate vs Magnesium L-Threonate

Mechanism

Iron is essential for hemoglobin (oxygen transport), myoglobin (muscle oxygen storage), cytochrome enzymes (electron transport chain — Complexes I, II, III, IV), cytochrome P450 enzymes (drug/hormone metabolism), catalase (H2O2 decomposition), ribonucleotide reductase (DNA synthesis), and aconitase (Krebs cycle). Iron bisglycinate (Ferrochel) uses amino acid chelation to bypass the normal DMT1/ferroportin pathway, instead being absorbed intact via PepT1 transporter. This mechanism avoids the GI side effects of ionic iron (free Fe2+ generates hydroxyl radicals via Fenton reaction in the gut lumen) and is not inhibited by phytates, tannins, or calcium.

Standard Dosing

25-36mg elemental iron (as bisglycinate) daily for deficiency correction

Timing

On empty stomach or with vitamin C for absorption. Alternate day dosing (every other day) may be superior due to hepcidin cycling. Separate from calcium, zinc, tea, coffee by 2+ hours.

Cycle Duration

Until ferritin >50 ng/mL, then reassess (typically 3-6 months). Not for ongoing supplementation unless chronic blood loss.

Side Effects

• GI distress (significantly less than ferrous sulfate)
• Constipation (less common with bisglycinate)
• Dark stools
• Nausea
• Iron overload if supplemented unnecessarily

Contraindications

• Hemochromatosis
• Iron overload conditions
• Thalassemia (without documented deficiency)
• Hemolytic anemias (unless also iron deficient)
• Chronic transfusion therapy

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Mechanism

Magnesium L-threonate (Magtein) was specifically developed by MIT researchers to cross the blood-brain barrier efficiently. L-threonate, a metabolite of vitamin C, acts as a carrier to increase brain magnesium concentration by ~15% (compared to negligible CNS penetration from other Mg forms). Elevated brain Mg2+ enhances NMDA receptor signaling fidelity, increases synaptic density in the hippocampus and prefrontal cortex, promotes BDNF expression, and enhances both short-term and long-term memory via potentiation of pre-synaptic release probability at hippocampal CA3-CA1 synapses.

Standard Dosing

1000-2000mg magnesium L-threonate daily (providing ~144mg elemental Mg per 2000mg)

Timing

Split dose: 1 capsule morning, 2 capsules before bed (or per product label). Evening dose supports sleep and overnight memory consolidation.

Cycle Duration

ongoing

Side Effects

• Drowsiness
• Headache (initial)
• Mild GI discomfort
• Cost (significantly more expensive than other Mg forms)

Contraindications

• Severe renal insufficiency
• Myasthenia gravis

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