Effect of calcium, phosphorus, magnesium, and aluminum on fluoride metabolism in man.

The studies of the interaction of fluoride with minerals in man have shown that: 1. in contrast to observations made in animals, the high intake of calcium, phosphorus, and magnesium in amounts that can be used in humans did not inhibit the intestinal absorption of fluoride in man; 2. the lack of effect of added calcium, given in divided doses, on the intestinal absorption of fluoride has relevance for the use of a high calcium intake during fluoride therapy for osteoporosis; 3. aluminum as the hydroxide, commonly used as an antacid in clinical medicine, significantly decreases the intestinal absorption of fluoride. This inhibitory effect, in conjunction with the known effects of aluminum-containing antacids in causing calcium loss as a consequence of phosphorus depletion, may contribute to the development of skeletal demineralization.