Are you Familiar with all the Tools to Reduce Prevalence of Iron Deficiency Anemia?
Whole grains, legumes and nuts provide plenty of minerals. However, they also contain high levels of phytate which binds with iron (Fe), calcium and zinc. Phytate-bound minerals cannot be absorbed. Iron bioavailability from vegetarian diets are lower (5-12%) compared to mixed diets (14-18%) and heme iron present in meat (25%). Phytates are a major reason that vegetarians and others who do not regularly eat red meat can become iron-deficient.
Iron-deficiency anemia (IDA) is the most common nutritional disorder globally. According to the World Health Organization, 30% of the world’s population, or 2 billion people, are anemic. One approach to reduce the prevalence of IDA is to increase the iron and zinc content of plant-based foods, i.e. biofortification. Selective plant breeding has successfully doubled the iron content of beans from 5 mg Fe / 100g to 10 mg Fe/100g.
Petry and colleagues measured iron bioavailability in biofortified beans fed to Rwandese women with low iron status. Meals prepared with biofortified beans had 54% more iron than those with regular beans. However, the biofortified beans also had more phytates which negatively affected iron bioavailability.
Iron absorption is strongly dependent upon phytate concentrations. Treating beans with phytase enzymes increased iron absorption. Dephytinization had a proportionally greater impact on beans with higher phytate concentrations. The authors recommend the development of high-iron beans with lower phytate concentrations.
The benefits of selective plant breeding programs can be enhanced by using enzymes (phytase) to degrade phytate. Koreissi-Dembele et al (2013) and Petry and colleagues added phytase during food preparation to reduce the phytate concentration. Phytases can effectively reduce the amount of phytate in the food being consumed.
Another strategy is to add phytases which can withstand gastric acidity at the point of consumption. The phytase will degrade phytate and liberate minerals within the lumen of the intestine. Using this approach to increase iron bioavailability, iron absorption was increased in young children eating a complementary food fortificant mixed with a cereal porridge. Moreover, combining phytases with micronutrient powders containing low amounts of iron may be potentially safer than providing caregivers with powders containing high amounts of iron.
In summary, with 2 billion anemic people and an increasing global population, there is an urgency to improve iron status globally. Iron fortification, including biofortification, phytases and vitamins which enhance iron absorption will all be part of the solution.
Petry N, Egli I, Gahutu JB, Tugirimana PL, Boy E, Hurrell R. Phytic acid concentration influences iron bioavailability from biofortified beans in Rwandese women with low iron status. 2014 J Nutr doi: 10.3945/jn.114.192989
Gibson RS, Baily KB, Gibbs M, Ferguson EL. A review of phytate, iron, zinc, and calcium concentrations in plant-based complementary foods used in low-income countries and implications for bioavailability. 2010 Food & Nutr Bull 31:134-146
Hurrell R, Egli I. Iron bioavailability and dietary reference values. 2010 Am J Clin Nutr doi: 10.3945/ajcn.2010.28674F
Donangelo CM, Woodhouse LR, King SM, Toffolo G, Shames DM, Viteri FE, Cheng Z, Welch RM, King JC. Iron and zinc absorption from two bean (Phaseolus vulgaris L) genotypes in young women. 2003 J Agric Food Chem doi: 10.1021/jf030151w
Cercamondi CI, Egli IM, Mitchikpe E, Tossou F, Hessou J, Zeder C, Hounhouigan JD, Hurrell RF. Iron biovailability from a lipid-based complementary food fortificant mixed with millet porridge can be optimized by adding phytase and ascorbic acid but not by using a mixture of ferrous sulfate and sodium iron EDTA. 2013 J Nutr doi: 10.3945/jn.113.175075
Koreissi-Dembele Y, Fanou-Fogny N, Moretti D, Schuth S, Dossa RAM, Egli I, Zimmerman MB, Brouwer ID. Dephytinazation with intrinsic wheat phytase and iron fortification significantly increase iron absorption from fonio (Digitaria exilis) meals in West African women. 2013 PLoS ONE doi: 10.1371/journal.pone.0070613
Troesch B, Egli I, Zeder C, Hurrell RF, de Pee S, Zimmerman MB. Optimization of a phytase-combining micronutrient powder with low amounts of highly bioavailable iron for in-home fortification of complementary foods. 2009 Am J Clin Nutr doi: 10.3945/ajcn.2008.27026