Dietary Requirements for Calcium

Normal, healthy adults must be assumed to be in a state of nutritional equilibrium — at least over a period of time. They must be taking in nitrogen, phosphorus, sodium and other elements at the same rate as they are excreting them. For some of these elements, the calculation of a body balance is very difficult, but in the case of calcium it is relatively simple. Discounting dermal losses [which may be quite significant (Charles et al. 1983)], the calcium balance is the difference between the dietary calcium on the one hand and the faecal and urinary calcium on the other.