Magnesium Deficiency and Anxiety, Insomnia, and Depression: Assessment and Ad-junctive Intervention in Psychiatric Practice

Abstract

Background: Magnesium (Mg) is an essential mineral involved in central nervous system homeost asis, energy metabolism, and mood regulation. A reliance on refined, processed foods and increase d urinary excretion driven by chronic psychosocial stress readily produce a latent Mg deficiency t hat is difficult to detect on routine blood tests. In psychiatric practice, Mg insufficiency may unde rlie nonspecific somatic complaints such as refractory vague gastrointestinal symptoms, chronic fati gue, irritability, eyelid twitching, and altered bowel habits.

Objective: This review organizes the relationship between Mg deficiency and depression, anxiety, and insomnia from the perspective of nutritional psychiatry, separating the evidence into pathophys iology, basic research, observational studies, and intervention studies, and proposes a multidisciplin ary adjunctive approach consistent with standard treatment.

Main Text: Basic research suggests that Mg deficiency contributes to hypothalamic-pituitary-adrena l axis overactivity, chronic low-grade inflammation, reduced gut microbial diversity, and impaired i ntestinal barrier function. At the molecular level, suppression of NMDA receptor function and GA BA-receptor-mediated modulation of neuronal excitation are postulated, although clinical efficacy in humans has not been established. Observational studies report a nonlinear association between Mg intake and depression risk, but causality remains unproven. Effects in intervention studies are lim ited, with clinical relevance suggested mainly in subgroups in whom deficiency is suspected. A no rmal serum Mg level does not exclude intracellular deficiency, and long-term use of proton pump inhibitors or diuretics is a recognized cause of drug-induced hypomagnesemia. Several psychotropic agents are reported to influence intracellular Mg concentrations, making attention to drug interacti ons and safety important.

Conclusion: Because latent Mg deficiency may aggravate mild depression, anxiety, and insomnia, dietary guidance and supplementation for deficient states have value as adjuncts, although they do not replace standard psychiatric treatment. In routine practice, a Food-first principle combined with assessment of somatic symptoms, dietary history, and concomitant medications, together with shar ed roles among nurses, pharmacists, and dietitians, is practical.