The Utilization of Calcium

Abstract

Studies have been made of the retention in the rat's body of calcium fed in various forms. When calcium was added to a low calcium but otherwise normal diet, including cod liver oil, in the form of calcium carbonate, calcium chloride, dicalcium phosphate, calcium gluconate, calcium lactate, whole milk powder, casec and Pablum, the percentage of the added calcium retained was essentially the same in each instance. With an adequate phosphorus and low calcium diet, the retention of calcium and phosphorus increases approximately in the ratio of 2:1 when extra calcium retention is brought about by the addition of calcium to the diet. In other words, in a diet adequate in phosphorus, the amount of phosphorus retained is dependent on the amount of calcium retained. The addition of calcium in the form of large amounts of spinach to a low calcium diet resulted in a reduction rather than an increase in the body calcium. This effect is probably due in part to the oxalic acid content of the spinach. The increase in the body calcium produced by the addition of different cereals has been studied. The inadequacy of an average human diet low in milk, as a source of calcium, has been biologically demonstrated. Not only is the calcium retention on this diet low but the percentage of the calcium retained is less than in the same diet with added milk.