Magnesium Deficiency—Not Supplementation—Causes Mood Disturbances
Magnesium supplementation does not cause mood swings; rather, magnesium deficiency is associated with mood disturbances including irritability, depression, and agitation. 1
Mood Effects of Low Magnesium
Low magnesium levels are linked to psychiatric symptoms, not magnesium supplementation:
- Hypomagnesemia causes neurological symptoms including irritability, confusion, and hallucinations in cancer patients and other populations 1
- Magnesium deficiency in women specifically led to altered mood and increased pain during the premenstrual phase 1
- Personality changes observed with magnesium deficiency include apathy, depression, agitation, confusion, anxiety, and delirium 2
- Animal studies demonstrate that magnesium-depleted diets produced depressive behaviors that were reversed by antidepressant drugs 2
Magnesium Supplementation Effects on Mood
The evidence shows magnesium supplementation improves rather than worsens mood:
- Magnesium preparations are used therapeutically for premenstrual tension syndrome and mood-related symptoms 3, 4
- Magnesium supplementation has demonstrated antidepressant-like effects in both preclinical and clinical studies 3
- A 2008 randomized trial showed magnesium was as effective as imipramine for treating depression in diabetics, without the side effects 5
- Magnesium supplements are considered a valuable addition to standard depression treatments with a beneficial safety profile 3, 2
Side Effects of Magnesium Administration
The documented adverse effects of magnesium relate to cardiovascular—not psychiatric—symptoms:
- Rapid intravenous magnesium administration produces vasodilation and hypotension, not mood changes 1
- Hypermagnesemia (excess magnesium >2.2 mEq/L) causes drowsiness, confusion, and depressed consciousness, but these are neurological depression effects from toxicity, not mood swings 1
Clinical Bottom Line
If a patient reports mood swings while taking magnesium, consider alternative explanations rather than attributing symptoms to the supplement itself. The scientific literature consistently demonstrates that magnesium deficiency—not supplementation—is associated with mood disturbances, and that correcting deficiency typically improves mood symptoms. 1, 3, 2