Comparison Study of Iron Bioaccessibility from Dietary Supplements and Microencapsulated Preparations

Iron deficiency is the most common form of malnutrition. Factors responsible for this so-called “hidden hunger” include poor diet, increased micronutrient needs and health problems such as diseases and infections. Body iron status can be increased by the intake of dietary supplements and fortified food. The aim of the present study was to compare iron bioaccessibility from commercial nutritional supplements and iron microcapsules. A comparison study was performed under conditions mimicking gastric and gastrointestinal digestion. A preparation of encapsulated ferrous sulphate or lactate and vitamin C, in a formula, showed bioaccessibility factors of up to 100% when digested individually, and around 60% in the presence of a food matrix. The degree of oxidation of the ferrous ions differed, depending on the type of preparation, the presence of vitamin C and the food matrix. The highest percentage content of ferrous ion, in the soluble fractions after gastrointestinal digestion, was shown by the preparation containing microencapsulated ferrous lactate or ferrous sulphate and vitamin C. Encapsulation seems to limit the interaction of iron with the food matrix and protect it against oxidation, thus making it more accessible for intestinal uptake.