Magnesium Glycinate

A highly bioavailable magnesium form that supports sleep, stress, and metabolic function.

MineralMagnesium BisglycinateChelated Magnesium

Magnesium glycinate is a chelated form of magnesium bound to the amino acid glycine. This combination provides excellent bioavailability with minimal GI side effects compared to other magnesium forms. Magnesium is involved in over 300 enzymatic reactions in the body, including energy production, muscle function, nervous system regulation, and blood sugar control. An estimated 50-80% of Americans are deficient.

Evidence-Based Benefits

Sleep Quality

Magnesium activates the parasympathetic nervous system and regulates GABA receptors, promoting relaxation and improving sleep quality. Glycine itself has independent sleep-promoting effects.

Stress & Anxiety Reduction

Modulates the HPA axis and cortisol response. Clinical trials show magnesium supplementation reduces subjective anxiety, especially in deficient individuals.

Muscle Function

Essential for muscle contraction and relaxation. Deficiency causes cramps, spasms, and impaired exercise performance.

Blood Sugar Regulation

Improves insulin sensitivity and glucose metabolism. Meta-analyses show significant HbA1c reduction with magnesium supplementation in diabetic patients.

Blood Pressure Support

Meta-analyses demonstrate modest but consistent blood pressure reduction with magnesium supplementation.

Bone Health

Magnesium is required for vitamin D activation and calcium metabolism. Approximately 60% of body magnesium is stored in bone.

Dosing Guide

Common Dose

200-400 mg elemental magnesium per day

Best Timing

Evening / before bed (leverages calming effects)

With Food?

Yes — take with a meal

Start with 200mg and increase gradually. Divide into 2 doses if taking more than 300mg. Magnesium glycinate is well-tolerated and rarely causes diarrhea unlike magnesium citrate or oxide.

Forms & Comparison

Magnesium Glycinate / Bisglycinate

Best for sleep, anxiety, and general supplementation. Highest bioavailability with fewest GI side effects.

Magnesium L-Threonate

Best for cognitive function — uniquely crosses the blood-brain barrier. More expensive.

Magnesium Citrate

Good bioavailability but can cause loose stools. Better for constipation.

Magnesium Oxide

Cheapest but poorly absorbed (4% bioavailability). Mostly useful as a laxative.

Magnesium Taurate

May be particularly beneficial for cardiovascular health due to taurine's cardiac effects.

Cautions & Interactions

High doses (>400mg) may cause loose stools, though glycinate form is best tolerated.
Caution with kidney disease — impaired magnesium clearance can cause toxicity.
May interact with antibiotics (tetracyclines, quinolones) — separate by 2 hours.
May interact with bisphosphonates (osteoporosis drugs) — separate by 2 hours.
May enhance effects of blood pressure medications.

Frequently Asked Questions

How do I know if I'm magnesium deficient?

Standard serum magnesium tests are unreliable — only 1% of body magnesium is in the blood. An RBC magnesium test is more accurate. Clinically, symptoms like muscle cramps, poor sleep, anxiety, and chocolate cravings suggest deficiency. Given that 50-80% of Americans are deficient, supplementation is reasonable for most people.

Can I take too much magnesium?

The upper tolerable limit from supplements is 350mg/day elemental magnesium. Higher doses are generally safe for healthy individuals but may cause diarrhea. Toxicity is primarily a concern with kidney impairment.

Glycinate vs citrate — which is better?

Glycinate for sleep and anxiety (better tolerated, glycine adds calming effect). Citrate for constipation relief (osmotic laxative effect). Both have good bioavailability.