Magnesium Supplementation for Anxiety
Magnesium supplementation may help alleviate anxiety symptoms, particularly in individuals with low magnesium status, though the evidence is suggestive rather than definitive. 1, 2
Evidence for Magnesium's Effect on Anxiety
A systematic review of available evidence suggests beneficial effects of magnesium on subjective anxiety in anxiety-vulnerable populations, though the quality of existing evidence is limited 1
In stressed but otherwise healthy individuals with low magnesium levels, supplementation significantly improved anxiety scores over an 8-week period, with most improvement occurring in the first 4 weeks 3
Five out of seven studies measuring anxiety-related outcomes reported improvements in self-reported anxiety with magnesium supplementation 2
Animal studies demonstrate that chronic magnesium supplementation produces a statistically significant decrease in anxiety levels without affecting locomotion 4
Dosage and Administration
Typical effective dosages in clinical studies range from 300-600 mg of elemental magnesium daily 3, 2
Magnesium oxide (12 mmol) administered at night may help with absorption, as nighttime is when intestinal transit is slowest 5
Liquid or dissolvable magnesium products are usually better tolerated than pills 6
Organic magnesium salts (aspartate, citrate, lactate) have higher bioavailability than magnesium oxide or hydroxide 6
Potential Benefits Beyond Anxiety
Magnesium supplementation may also improve quality of life measures in stressed individuals 3
Some evidence suggests magnesium may help with sleep quality, which could indirectly benefit anxiety symptoms 2
Magnesium replacement is recommended for management of hypomagnesemia, which can cause irritability and other neurological symptoms 6
Limitations and Considerations
The anxiolytic effect of magnesium supplementation may wash out after discontinuation (observed after 12 days in animal studies) 4
Negative results were more common in populations with underlying endocrine factors contributing to their symptoms (premenstrual symptoms and postpartum women) 2
Side effects of excessive magnesium supplementation may include gastrointestinal intolerance, muscle weakness, flushing, hypotension, bradycardia, blurred vision, and cognitive effects 6
It is recommended to start with the recommended daily allowance (350 mg daily for women; 420 mg daily for men) and increase gradually according to tolerance 6
Conclusion
While the evidence for magnesium's effect on anxiety is promising, particularly for those with low baseline magnesium levels, the quality and quantity of research is still limited. The most recent and comprehensive review suggests magnesium supplementation is likely useful for mild anxiety, especially in those with low magnesium status 2. However, larger randomized clinical trials are needed to establish definitive efficacy and optimal dosing regimens.