(P30-018-25) Predicting Calcium Adequacy: Application of Calcium Bioavailability Predictive Equation

Objectives: A calcium bioavailability predictive equation was developed from a model of fractional calcium absorption using calcium load and the two major inhibitors, oxalic acid and phytate from published studies. Knowing the bioavailability of nutrients from foods allows for more accurate assessments of mineral deficiencies at individuals, groups, and geographical regional levels. This information can inform policies and strategies to reduce gaps in nutrient needs relative to requirements. This study reports initial steps of applying the algorithm to food composition databases.

Methods: Calcium composition of food was collected from USDA FoodData Central (FDC). Phytate composition of food was sourced from the FAO/INFOODS/IZiNCG Global Food Composition Database for phytate. Oxalate data was collected from various scientific publication. Additional calcium, phytate, and oxalate data for foods not present in FDC and/or PhyFoods Composition were collected from the literature. Food balance data were collected from FAO Food Balances (2010). Food descriptions from oxalate studies were mapped to equivalent foods in Food Data Central and PhyFoodComp. Fractional calcium absorption was calculated using the formula described in Weaver et al (2024). The fractional calcium value was applied to each food item to assess the calcium bioavailability.

Results: A list of foods, along with their corresponding calcium bioavailability values, was generated.

Conclusions: Having calcium bioavailability values for foods extends the ability to evaluate calcium adequacy, moving beyond the current approach of using calcium content alone.

Funding Sources: Funding for this study was provided by The International Life Sciences Institute (ILSI), US & Canada, through a grant from the Sustainable Nutrition Initiative (SNi), a not-for-profit program of the Riddet Institute at Massey University in New Zealand, and Balchem Corporation.