Food-Based Approaches

This toolkit advocates for a diverse diet that would provide adequate sources of all essential nutrients as well as chemicals, often called phyto-chemicals, in foods that have benefits for health. Because of the central role of iron in red blood cell production, the Toolkit will focus on food-based approaches to improve dietary intake of iron, although it recognizes the importance of food and a diverse diet to ensure adequate health and nutrition in general.

There are several micronutrients in addition to iron that are involved in red cell production and function. These include vitamins (A, B-12, folic acid, and possibly B-6, C, and riboflavin) and copper. A non-diverse diet increases the risk of micronutrient deficiencies including iron deficiency (Arimond, et. al., 2010). A recent paper (Lee, et al., 2012) on dietary takes in low- and middle-income country found the diets of pregnant were predominantly cereal-based and iron and folic acid intakes were lower than Estimated Average Requirements, followed by calcium and zinc. A 2010 publication on the Global Burden of Disease demonstrated that inadequate intake of nutritious foods (i.e., fruits, nuts and seeds, whole grains, vegetables, omega-3 fatty acids, and fiber) and excessive intake of high processed meat accounted for 20% (or 7 out of 33 risk factors) contributing to the global burden of disease.

Iron types, Requirements, and Bioavailability

There are two forms of iron, heme and non-heme iron, in food. One form of iron is called “non-heme” iron, and it is present in a number of plants including some cereals, pulses, and vegetables. Non-heme iron is not well-absorbed because there are other substances in these foods, often called iron inhibitors, which decrease non-heme iron’s bioavailability. Only 5-12% of non-heme iron is absorbed from the diet. Reducing inhibitors and increasing enhancers of non-heme iron absorption also will determine absolute iron take in the deficient individual. Click here for the recommended iron intake based on varying dietary iron bioavailability. Some types of food processing techniques decrease the inhibitors of non-heme iron in food. These methods include thermal processing, mechanical processing, soaking, fermentation, and germination/malting and a combination of these methods has been found to improve iron status (Hotz and Gibson, 2007).  Animal flesh (meat including organs) and vitamin C in fruits and vegetables also improves the bioavailability of non-heme iron.

The other form of iron is called “heme” iron which is present only in animal flesh and organs and fish. Heme iron is more bioavailable with 15% to 35% of heme iron absorbed. In many countries, meat is expensive and consumed in only on special occasions, if at all. Women and children, who have the highest requirements, may not have access to these foods when they are available to the family. Even small amounts of the heme iron in meat increases the absorption of non-heme iron. Click here to view the enhancers and inhibitors of iron absorption. Click here for more information about the bioavailability of iron in foods.

The main determinant of iron absorption, however, is the iron status of the individual. Iron absorption increases when the body needs iron. The highest absorption occurs when an individual’s iron requirements increase (e.g., pregnancy or growth in young children) or the individual is severely iron deficient. When an individual has enough iron (is iron replete), little is absorbed because the body regulates the absorption of iron tightly because, unlike other minerals, the body has no mechanism for iron excretion (Hurrell and Egli, 2010).

Food-based approaches covered in this Toolkit include Agriculture Production and Markets and Fortification and Bioavailability.

Behavior Change Communication

All food-based approaches need complementary behavior change communications to ensure each approach is effective. Consumers need to be educated to use and purchase available nutrient-rich foods and food products. Mothers and families need to prioritize giving these foods to young children and ensure they consume them, when they are available. In many cultures, feeding children animal products is delayed until children are older than one year of age or until they have their first set of teeth. There also is a belief that young children do not need these foods when, in fact, children 6-12 months of age have the highest requirements for iron per body weight. A program in Mozambique which combined promoting and supporting the production of orange-flesh sweet potato (OFSP) with nutrition education about infant and young child feeding increased intakes of OFSWP and beta-carotene and increased serum retinol values in children involved in the program (Low, et al., 2007). For more information about infant and young child feeding click on the following: WHO, IYCN, and Alive and Thrive.