Dialyzable Calcium and Phosphorus in Mexican Diets High in Insoluble Fiber

Adequate calcium (Ca) intake is important to prevent osteoporosis. Beans, corn, and flour tortillas are the principal energy sources in the typical Mexican diet and Ca comes primarily from corn tortillas. Total dietary fiber intake is about 45 g/d. Intake of dairy products is low and only occasional. The objective of this study was to determine by in vitro methods, the percent dialyzable Ca and P in typical Mexican diets. Tortillas made from a mixture of lime-treated corn and a commercially prepared corn flour had 162.1 mg of Ca/100 g, dry weight basis, compared to tortillas made with corn flour only with a value of 106.2 mg/100 g. Phosphorus (P) content was 119.2 and 101.8 mg/100 g, respectively. The diet formulated with corn tortillas as the only source of Ca had 6% dialyzable Ca and 3% dialyzable P. The diet containing a mixture of animal and vegetable products showed significant (α = 0.05) higher Ca dialyzability, 8%. P dialyzability in this diet was 4%. The results indicate that Ca in the typical Mexican diet is not very available.