Effect of ascorbic acid on the absorption of zinc and calcium in man.

The effect of ascorbic acid on the absorption of zinc and calcium, was studied in healthy subjects by a radionuclide technique with 65Zn and 47Ca and whole body retention measurements. Addition of 100 mg of ascorbic acid to a water solution of 40 or 200 mumol zinc and 1 g of ascorbic acid to a high phytate meal with wholemeal bread had no effect on zinc absorption. Neither did 1 g of ascorbic acid added to 6.4 mmol of calcium influence the retention and calculated absorption of calcium. The results suggest that ascorbic acid does not affect the absorption of normal dietary levels of zinc and calcium.