Myths vs facts: Magnesium and fatigue

The claim that magnesium universally cures fatigue is a myth. Fact: Magnesium supplementation can reduce fatigue in individuals with confirmed deficiency, such as those with type 2 diabetes, older adults, or people under chronic stress. However, for the general population without deficiency, evidence does not support a significant anti-fatigue effect. Many factors cause fatigue – poor sleep, iron deficiency, thyroid disorders, depression, or overtraining – and magnesium alone rarely addresses these. High-dose supplements (>350 mg/day) may cause gastrointestinal discomfort, diarrhea, and, in renal impairment, dangerous electrolyte imbalances. A serum or RBC magnesium test can guide supplementation. Evidence: human-moderate (RCTs in deficient groups) but mixed for non-deficient. Safety: avoid self-supplementation without lab confirmation, especially with kidney issues.