Vitamin
B-Complex
A group of eight B vitamins that work together to support energy metabolism, nervous system function, and red blood cell production.
Moderate Evidence
Strong Evidence Mineral
Magnesium Glycinate
Magnesium glycinate is a chelated form of magnesium bound to the amino acid glycine. This combination offers superior bioavailability compared to common forms like magnesium oxide (which has only 4% absorption) while being notably gentle on the digestive system. Magnesium is a cofactor in more than 300 enzymatic reactions in the human body, required for ATP production, protein synthesis, blood sugar regulation, blood pressure management, nerve transmission, and muscle contraction. It is essential for bone structure and plays a direct role in the active transport of calcium and potassium across cell membranes. Despite its critical importance, roughly 50% of Americans fail to meet the recommended daily intake. Subclinical deficiency — levels low enough to impair function but not low enough to trigger obvious symptoms — may affect up to 60% of the population. The glycine component provides additional benefits: glycine is an inhibitory neurotransmitter that supports sleep quality and has calming effects on the central nervous system, making magnesium glycinate particularly well-suited for evening use.
Updated March 1, 2026This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any supplement or medication regimen.
Benefits & Uses
Corrects widespread magnesium deficiency. Supports 300+ enzymatic reactions. Improves sleep quality (both from magnesium and glycine). Reduces muscle cramps and tension. Supports healthy blood pressure. May reduce anxiety and stress. Supports bone mineral density. Better tolerated than oxide or citrate forms.
Side Effects & Precautions
Generally very well tolerated — the glycinate form causes significantly less GI distress than oxide or citrate. Mild drowsiness (beneficial if taken at bedtime). At very high doses, loose stools. Rarely, low blood pressure in sensitive individuals.
Dosage & Administration
200-400mg elemental magnesium daily (this equates to roughly 1400-2800mg of magnesium glycinate compound). Take in the evening for sleep support, or split doses morning/evening. Can be taken with or without food. Start at the lower end and increase gradually to assess tolerance. The RDA is 400-420mg for adult men and 310-320mg for adult women (from all sources combined).
Contraindications
Severe kidney disease or renal failure (impaired magnesium excretion). Myasthenia gravis. Heart block. Individuals on dialysis should avoid supplemental magnesium without nephrologist guidance.
Known Interactions
| Substance | Type | Severity | Description |
|---|---|---|---|
| Antibiotics (tetracyclines, fluoroquinolones) | moderate | Magnesium chelates with these antibiotics in the GI tract, forming insoluble complexes that dramatically reduce antibiotic absorption. Take magnesium at least 2 hours before or 4-6 hours after these antibiotics. | |
| Bisphosphonates (alendronate, risedronate) | moderate | Magnesium can interfere with the absorption of bisphosphonate medications used for osteoporosis. Take bisphosphonates first thing in the morning on an empty stomach, and wait at least 2 hours before taking magnesium. | |
| Blood pressure medications | minor | Magnesium has mild antihypertensive effects. When combined with blood pressure medications, the additive effect may cause excessive blood pressure reduction in some individuals. Monitor blood pressure when starting magnesium supplementation. |
Sources
Related Supplements
Mineral
Iron
An essential mineral required for oxygen transport in blood and energy production, commonly supplemented for anemia.
Strong Evidence
Mineral
Magnesium
An essential mineral involved in over 300 enzymatic reactions, commonly supplemented for muscle relaxation, sleep, and stress support.
Moderate Evidence
Vitamin
Vitamin C
A water-soluble antioxidant vitamin essential for immune function, collagen synthesis, and iron absorption.
Related Articles
foundations
Folate vs. Folic Acid for MTHFR and Homocysteine: What Research Really Says
A focused, evidence-based guide to folate vs. folic acid for MTHFR and homocysteine—what’s proven, what’s hype, and how a food-first approach supports methylation.
7 min read
Moderate Evidence foundations
Vitamin C and Collagen Synthesis: What It Means for Skin, Wounds, and Connective Tissue
Vitamin C’s unsung role as a collagen cofactor: what research suggests for skin integrity, wound healing, and connective tissue—plus insights on amla, acerola, and camu camu.
7 min read
Moderate Evidence foundations
Homocysteine: What This Blood Marker Tells You About B Vitamins and Methylation
A focused guide to homocysteine as a marker of B‑vitamin status and methylation—what raises it, what it predicts, how food patterns may help, and where the evidence is strong vs. mixed.
8 min read
Moderate Evidence Health Disclaimer
This content is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting, stopping, or changing any supplement or medication regimen.