Assessing bioavailability and nutritional value of microencapsulated minerals

This chapter focuses on the bioavailability of mineral compounds and the methodologies used to assess the bioavailability of microencapsulated mineral formulations. One of the well-known nutritional deficiencies for the treatment of which microencapsulated compounds have been extensively investigated in recent years is iron deficiency and iron deficiency anemia. The chapter mainly discusses methods and results of these investigations. Iron is a trace element which has a particular position among minerals for human nutrition: as there is no known excretion mechanism for iron in mammals, iron metabolism is regulated at the site of absorption and bioavailability is of paramount importance in maintaining iron balance. Methodologies to estimate, measure, and assess mineral bioavailability can be distinguished into four categories, listed in order of suitability for high throughput screening: in vitro methods with and without the use of Caco-2 cells; animal-based models; studies in human subjects using tracers; and double-blind, randomized controlled trials.