Using a rat model, calcium bioavailability (BV) from tofu, tortillas, nonfat dry milk (NFDM) and mozzarella cheese was compared to a control diet supplemented with calcium carbonate (CaCOj). The above diets were each formulated with and without 0.05% ascorbic acid. When comparing different calcium sources, the relative BV from tofu (107%) was significantly higher (p < 0.05) than from tortillas (93%) or NFDM (95%).Calcium BV from tofu, cheese (105%) and CaCO, (100%) was not different. Vitamin C supplementation has no significant effect on calcium BV. Although some differences were noted, overall calcium BV from each of the tested products was excellent.