About 50% of magnesium in the body is found associated with bone matter. It is also found in extracellular fluids & in soft tissues, particularly in the muscle tissues. Overall, magnesium is involved in over 300 different enzymatic & metabolic processes, including energy production, bone development & growth, & for proper nerve transmission, muscle contraction & cardiovascular function. Heavy drinkers, the elderly, diabetics, those with gastro-intestinal disorders, menstruating & menopausal women, & those who use oral contraceptives or diuretics may have an increased dietary requirement for magnesium