It has recently been discovered that both birth weight and the infants’ nutrition supply are important risk factors for later morbidity in adulthood. Due to high nutritional requirements, infants with low birth weight are at risk of developing nutrient deficiencies during their first year of life, including iron deficiency. Iron is necessary for the production of hemoglobin for the blood, and also for the development of the brain. Iron deficiency in infants has been shown to be associated with poor neurological development.
The present study included 285 children with marginally low birth weights (2000-2500 g). They were randomly divided into three groups that were given different amounts of iron drops (0, 1, or 2 mg per kg daily) from the age of 6 weeks to 6 months. Among children who were given placebo drops (no iron) 36 % had iron deficiency and 10% iron-deficiency anemia at the age of 6 months, whereas the corresponding figures for children who received 2 mg of iron were 4% and 0%. At greatest risk of developing iron deficiency were those children who were fully breast-fed at the age of 6 weeks. They ran an 18% risk of developing iron-deficiency anemia by the age of 6 months if they did not receive iron drops.
The study indicates no negative effects from iron drops on the children’s growth, infections, or other morbidity. Most children with marginally low birth weights in Sweden are considered healthy and are not given iron drops, although routines differ from one hospital to another. The study indicates that these children should be given iron drops, as they otherwise run a high risk of developing iron deficiency and anemia.
What effects iron deficiency has on brain development is as yet unclear, but the Umeå researchers will be following these children up to the age of 7 years and test their intellectual development, the occurrence of behavioral problems, and attention problems in order to find out whether iron supplements for infants have any effect on brain function at school age.
The findings will have a great impact on nutrition recommendations for children with marginally low birth weights in Sweden and abroad, and they will hopefully lead to improved health in these children when they reach school age. In Sweden 3.5% of all newborns have low birth weights (under 2 500 grams), which means that some 300,000 Swedes have had a low birth weight. Most of these people had only marginally low birth weights (2000-2500 g).
The study was performed by Magnus Domellöf and his doctoral student Staffan Berglund, both with Umeå University, in collaboration with Björn Westrup, Karolinska Institute.
Reference: Iron Supplements Reduce the Risk of Iron Deficiency Anemia