Plasma magnesium levels in a population of psychiatric patients: correlations with symptoms.

Plasma magnesium levels were tested in a group of 155 psychiatric in-patients with a variety of diagnoses and were correlated with the severity of their symptoms. We hypothesized that lower Mg levels would correlate with a higher degree of anxiety, tiredness and other symptoms characteristic of Mg deficiency. No such correlations were observed. However, Mg levels varied widely, with 22.4% below, and 10.4% above the normal range. There was a strong association for more disturbed and excitable patients to have abnormal (either high or low) levels. We speculate that more disturbed patients might have some abnormality of Mg metabolism with possible therapeutic implications.