The use of solubility, dialyzability, and Caco-2 cell methods to predict iron bioavailability.

An update on in vitro methods employed to assess iron bioavailability is presented. Solubility and dialyzability are not useful predictors of iron absorption, whereas Caco-2 cell models provide useful comparisons on the availability of iron from different sources. Strengths and weaknesses of in vitro approaches are briefly described, including the need to characterize Caco-2 cells in order to interpret results correctly. Further developments are required to refine Caco-2 model systems, including optimization and standardization of methods.