Iron deficiency anaemia (IDA) is the most common nutritional problem affecting infants with 60% of 6-12 month old babies in the UK having low dietary iron intake, a key risk factor for developing IDA. Early childhood is a time of vulnerability as iron deficiency anaemia in this period may be associated with impaired development, especially if a baby had low iron stores at birth eg. as a result of prematurity or low birth weight. It’s also a time of rapid physical growth, brain and nervous system development, and a time when dietary iron needs are at their highest. Various risk factors are known to contribute: particularly premature birth, low birth weight, maternal iron deficiency and poverty. Iron supplementation may not adequately correct IDA in more extreme cases, and so infant feeding practices including the introduction of solids are important considerations. Iron supplementation requires medical or dietetic guidance, because iron overload can be harmful. The body is not able to excrete or get rid of excess iron, which is stored in the liver and spleen. For this reason, iron absorption is limited (by the gut) to around 15-20% and this becomes relevant when thinking about choosing iron-rich foods to offer, whether plant or animal and which foods improve or limit absorption. Here I provide some information around infants’ nutritional needs, dietary sources of iron, infant feeding practices and the introduction of iron-rich foods.
Infants’ Nutritional needs and Dietary sources of iron
Iron is an essential micronutrient required to make haemoglobin, brain and nervous system development, and protection from infection. Iron is the red pigment in haemoglobin, which carries oxygen around the body within the red blood cells. IDA means that the blood carries less oxygen than the body needs and infants with IDA will be pale and tired, have poor resistance to infection, and their general health, appetite, and vitality is poor. Typically, infants don’t show any signs in the early stages of IDA, and it commonly goes undiagnosed until they become symptomatic. Iron needs are highest in infants aged 6-12 months, term babies will used up all their iron stores, which built up during the last trimester of pregnancy, and dietary iron needs rapidly increase. Introducing iron-rich foods is critical at this age; not only does this provide essential dietary iron, but introducing those foods at this age helps establish familiar tastes, smells and textures of iron-rich foods like red meat, liver, egg yolk and also apricots, dried fruits, green vegetables, lentils, avocado, oily fish, seed and nut butter. Many cereals are fortified with iron, and since 1998, white wheat flour is fortified with 1.65mg iron per 100g. 7.8mg of iron is the reference daily intake for a healthy, term baby. The reference daily need for women of child bearing age is 14.8mg.
Infant Feeding practices and the Introduction of Iron-rich foods
Breast-fed infants need iron-rich foods on a daily basis from the weaning period 6-12 months because breast milk contains very little iron. Formula-fed infants also need to become familiar with iron-rich foods, even although iron-fortified formula will meet their iron needs beyond 6 months. Becoming familiar with the smells, tastes and textures of iron -rich foods like red meat, egg yolk and green vegetables, at an early age will help acceptance of these foods, prior to natural developmental phase of food refusal during toddlerhood. Toddlers who have eaten a wide variety of foods from 6-12 months (in the sensitive window) are less fussy because these foods are more familiar and they have practiced eating them. Those infants will also have developed a range of feeding skills, which supports eating better during toddlerhood. Drinking iron-fortified formula does protect against IDA, however, for longer-term feeding practices, introducing these more challenging tastes and textures during the sensitive window, provides more varied and robust nutrition going forward. First formula milks, those with a higher ratio of whey, are best suited for all babies until 1 year for many reasons, with improved absorption of nutrients including iron.