Magnesium is an essential cofactor in over 300 enzymatic reactions in the human body, playing a central role in GABA neurotransmitter regulation and muscular relaxation.
Which Magnesium Form Is Best for Sleep?
- Magnesium Bisglycinate: Bound to the calming amino acid glycine. Highly bioavailable and gentle on the digestive system; top choice for sleep and anxiety.
- Magnesium L-Threonate: Crosses the blood-brain barrier effectively to support cognitive function, synaptic plasticity, and calm.
- Magnesium Citrate: Good bioavailability with mild osmotic laxative properties.
- Magnesium Oxide: Poor bioavailability (~4%); primarily used as a laxative rather than for sleep support.
Recommended Timing & Safety
Take 200–400 mg of elemental magnesium with dinner or 30–60 minutes before bed. Consult your doctor if you have kidney disease or take certain prescription medications.