Magnesium

WHAT IT DOES

• Reduces blood pressure — Grade B evidence from 38 studies (2,709 participants). Moderate improvement, particularly in people with uncontrolled hypertension.
• Improves blood sugar control — Grade B evidence. Reduces fasting glucose, HbA1c, and insulin levels in type 2 diabetes.
• Supports sleep quality — Moderate evidence for improved sleep, especially in deficient individuals.
• Reduces pre-eclampsia risk — Grade A evidence. Important for pregnancy.
• Decreases muscle soreness — Grade B evidence. Reduces exercise-induced muscle damage markers.
• Reduces oxidative stress — Grade B evidence from 3 studies. Lowers inflammatory biomarkers.

OPTIMAL DOSAGE

DRUG INTERACTIONS

SAFETY PROFILE

Side Effects

Oral (relevant to supplements):

• Common: Diarrhea (most common — worse during high doses and in older adults; magnesium glycinate causes less), abdominal pain, bone pain
• Rare: Gastrointestinal obstruction (case reports with magnesium oxide at 1,500-3,000mg/day — from bezoar formation)

Intravenous/Intramuscular (medical settings only):

• Muscle weakness, tingling, skin flushing, sweating, nausea, vomiting, drowsiness, confusion, headache, dizziness, dry mouth, blurred vision, reduced blood pressure, tachycardia, respiratory depression, allergic reactions (rare)

Drug Interactions

△ KEY RULE: Take magnesium at least 2 hours BEFORE or 4-6 hours AFTER these medications to reduce interaction risk.

Nutrient Depletions (Drugs That Deplete Magnesium)

These medications can lower your magnesium levels — supplementation may be needed:

• Proton pump inhibitors — chronic use can cause severe, supplement-resistant depletion
• Thiazide diuretics — prolonged/high-dose use, especially in elderly
• Tacrolimus — increases urinary magnesium loss
• Hormonal contraceptives — can decrease Mg levels over time
• Cisplatin, amphotericin B, aminoglycosides, foscarnet, cetuximab — various oncology/antimicrobial drugs
• Insulin — elevated insulin can redistribute magnesium
• Alcohol — excessive consumption depletes magnesium

Precautions

• Pregnancy: Safe. Supplementation is both safe and potentially beneficial. Keep supplement dose under 350mg/day. IV magnesium during labor may slightly increase cesarean risk (~5%).
• Breastfeeding: Safe. Breast milk magnesium changes minimally with maternal supplementation.
• Children: Safe at age-appropriate doses.
• Kidney disease: Use with extreme caution. Kidneys regulate magnesium balance. Impaired kidneys can't clear excess magnesium, leading to potentially fatal hypermagnesemia. Only supplement under medical supervision.
• Bleeding risk: Use caution if you have a clotting disorder. High-dose oral magnesium (800-1,200mg/day) may reduce clotting, though clinical significance is unclear.
• Hypermagnesemia warning: Symptoms include nausea, dizziness, confusion, drowsiness, muscle weakness, low BP, blurred vision. Risk increases above 1,000mg/day supplemental and with impaired kidney function.

Quality Concerns

Nearly 60% of tested magnesium supplements (Poland study) had amounts differing from the label — ranging from 304% more to 98% less than stated. Some contained trace lead and uranium (unclear if dangerous). One German manufacturer's products were contaminated with anabolic steroids. Dose AI strongly recommends third-party tested products.

WADA Status

Not Prohibited. Not on the 2026 WADA list. However, cross-contamination risk exists (anabolic steroid contamination documented in 2005). Athletes should use NSF Certified for Sport or Informed Sport products.

WHO SHOULD BE CAREFUL

QUALITY CONCERNS

HOW SCAN DOSE SCORES THIS

CLINICAL REFERENCES