Magnesium

Powers every cell

ATP must bind magnesium to form Mg-ATP, the biologically active form. Without magnesium, cellular energy use is impaired — magnesium is required for energy metabolism, not just supportive of it. It is a cofactor in over 300 enzymatic reactions, particularly in energy metabolism, neuromuscular function, and cellular signaling.¹

Calmer mind, better sleep

Regulates neurotransmission and synaptic plasticity; supports GABA activity for a calming effect. Low magnesium is linked to increased neuronal excitability.²

Supports relaxation via GABA and nervous system regulation; associated with improved sleep quality, though the evidence is mixed-but-supportive rather than settled.³ (Moderate)

Relaxes muscles

Required for muscle relaxation (it counterbalances calcium) and helps prevent cramps and spasms. More broadly, it regulates ion channels (Ca²⁺, Na⁺, K⁺) and stabilizes membrane potential — see Calcium, Sodium, Potassium.

Steady heart rhythm

Regulates cardiac rhythm and electrical stability; imbalance can contribute to arrhythmias.¹

Better blood sugar control

Required for insulin receptor signaling (tyrosine kinase activity).⁴ Low magnesium is associated with increased insulin resistance and type 2 diabetes risk,⁵ and supplementation can improve insulin sensitivity and glucose control.⁶ Magnesium-dependent ATP is required for glucose metabolism generally. (Moderate — associational + some interventional support)

Calms inflammation

Helps regulate inflammation and oxidative stress.²

Forms & intake

Roughly 300–420 mg/day, varying by sex and age.¹ Cannot be synthesized — must come from diet. Bioavailability varies significantly by form; organic salts (citrate, glycinate) are generally better absorbed than inorganic forms like oxide.

• Magnesium glycinate (bisglycinate) — chelated with glycine for improved absorption and less laxative effect; may support nervous system/sleep via the glycine component itself (see Glycine / Collagen). This is the form the Metabolic Health hub's Tier 1 supplement entry specifically recommends, for absorption and GI tolerance.
• Magnesium citrate — relatively high absorption; osmotic activity draws water into the intestines (laxative effect); used for constipation and general supplementation.
• Magnesium oxide — high elemental magnesium content but poor bioavailability; primarily acts as a laxative/antacid.
• Magnesium threonate — proposed to cross the blood-brain barrier more effectively; limited human evidence, mostly preclinical. (Animal–in-vitro)
• Magnesium malate — bound to malic acid (a TCA-cycle intermediate); sometimes used for fatigue, but evidence is limited.

Top foods

• Pumpkin seeds
• Spinach
• Avocado
• Dark chocolate

Deficiency & safety

Neuromuscular: cramps, tremors. Cardiovascular: arrhythmias. CNS: anxiety, poor sleep.¹