A team of American, Austrian and Israeli researchers has found that heart disease patients tend to have lower intracellular magnesium levels than do healthy people. Their study involved 187 patients (151 men and 36 women) who had undergone coronary bypass surgery or angioplasty or had suffered a heart attack. The patients were randomized to receive 365 mg of elemental magnesium (in the form of citrate) daily or a placebo for six months. The average intracellular magnesium level (analyzed in scraping from under the tongue) in the entire group was 33.5 mEq/L, which is well below the normal level of 37.9 mEq/L. About 75% of participants in the US and Israel were found to be magnesium deficient. At the end of the six months the magnesium level in the supplemented group had increased to an average of 35.5 mEq/L versus 32.6 in the placebo group. The participants were given a complete medical examination, including a treadmill test at the beginning and end of the study. Patients in the magnesium- supplemented group increased their exercise duration by 14% over the six months while no change was observed in the placebo group. Instances of exercise-induced chest pain also decreased substantially in the magnesium group. Only 8% of the magnesium-supplemented patients experienced pain at the end of the six months versus 21% in the placebo group. The researchers conclude that coronary artery disease may be associated with a magnesium deficiency and that magnesium supplementation is an inexpensive and safe method of improving the quality of life for heart disease patients.
Shechter, Michael, et al. Effects of oral magnesium therapy on exercise tolerance, exercise-induced chest pain, and quality of life in patients with coronary artery disease. American Journal of Cardiology, Vol. 91, March 1, 2003, pp. 517-21