“…The bioavailability of magnesium may be affected by several dietary factors such as phosphorus, calcium, sodium or protein. It is known that high phosphate diets can decrease intestinal magnesium absorption due to the ability of phosphate to bind magnesium (Reinhold et al, 1991), whereas high sodium and calcium intake may result in increased renal magnesium excretion (Kesteloot & Joossens, 1990). In addition, dietary protein may also influence magnesium utilization; magnesium balance is negative when protein intake is less than 30 g/day, due to a high mineral excretion in urine and feces (Hunt & Schofield, 1969) whereas higher protein intakes, around 94 g/day, also may increase renal magnesium excretion (Mahalko et al, 1983), since the acid load increases urinary magnesium excretion (Wong et al, 1986).…”