BIOAVAILABILITY OF CALCIUM IN BREADS FORTIFIED WITH DIFFERENT CALCIUMSOURCES

This study used young rats as the test model to examine the relative b ioavailability (RE) of calcium (Ca) in breads fortified with five diff erent Ca sources. These sources included two inorganic (Ca carbonate a nd Ca sulfate) and two organic (Ca citrate and Ca lactate) Ca sources, and a brandname Ca supplement. RE was assessed based on rats' femur C a content and Ca absorption data. No differences of any physiological significance were observed in RE of Ca among the five sources tested. Compared to Ca carbonate (bioavailability arbitrarily set at 100%), RB of Ca in Ca sulfate was 105%, in Ca citrate 103%, in Ca lactate 102%, and in the Ca supplement 102%. This suggests that foods fortified wit h Ca carbonate or Ca sulfate, which are commonly used for this purpose , may be as good a source of utilizable Ca as more expensive Ca source s such as prescribed or nonprescribed Ca supplements.