Assessment of magnesium status.

The adult human body contains approximately 24 g (1 mol) of magnesium--about half in bone and half in soft tissues. Only about 0.3% of the total body magnesium is present in serum, yet the majority of analytical data obtained is from this body fluid. Assessing the magnesium status of an individual is difficult, there being at present no simple, rapid, and accurate test to determine intracellular magnesium, but determination of total and free magnesium in tissues and physiological tests provide some information. Changes in magnesium status have been linked to cardiac arrhythmias, coronary heart disease, hypertension, and premenstrual syndrome. A better understanding of magnesium transport and of factors controlling magnesium metabolism is needed to elucidate the role of magnesium in disease processes.