LACK OF EFFECT OF ORAL MAGNESIUM ON HIGH BLOOD PRESSURE - A DOUBLE-BLIND STUDY

Seventeen unselected patients with mild to moderate essential hypertension and whose average supine blood pressure after 2 mo. observation with no treatment was 154/100 mm Hg were entered into a double blind randomized crossover study of 1 mo.''s treatment with magnesium aspartate (15 mmol Mg./day) and treatment with placebo for a further month. This preparation of Mg was well tolerated and did not cause diarrhea. Despite a significant increase in plasma Mg concentration and a significant increase in urinary excretion of Mg while taking Mg aspartate there was no fall in blood pressure compared with either treatment with placebo or values before treatments. The results provide no evidence for a role of dietary Mg in the regulation of high blood pressure and are contrary to recent speculations.