Iron fortified infant foods may not be delivering: Study

In a special article written for the journal Nutrition Reviews​, Prof. Richard Hurrell reports that iron enriched complementary foods, designed for infants and young children need to be looked at in greater detail, in order to assess if they are delivering enough iron to deficient children.

“Iron-deficient infants and young children may absorb iron from ferrous fumarate less well than iron from ferrous sulphate … complementary foods targeted at such infants and young children should contain more iron,” ​wrote Prof. Hurrell of the Institute of Food Science and Nutrition at the Swiss Federal Institute of Technology (ETH), Zurich.

Widespread deficiency​

Iron deficiency in infants and young children is widespread globally, especially in developing countries, and can damage normal brain development, have serious detrimental effects in development.

Iron-deficient children have been reported to have lower mental, social, emotional, and motor development scores than infants with normal iron status.

Breast milk is low in iron, and iron stores in the liver of infants born at term only last between four and six months, therefore the addition of iron in complementary infant foods is important for healthy development.

Ferrous sulphate, ferrous fumarate, and electrolytic iron powder are recommended for the fortification of complementary foods by the World Health Organization and the Pan American Health Organization.

Ferrous fumarate (FF) is especially recommended for use because of its good sensory properties – ferrous sulphate (FS) has been shown to cause unacceptable sensory changes to food formulation.

The new review evaluated the value of ferrous fumarate and ferrous sulphate in the fortification of foods for infants and young children.

Less effective​

The review states that foods fortified with ferrous fumarate would be expected to be less effective than those fortified with ferrous sulphate, claiming iron absorption by infants and young children from FF fortified foods is only about 30 per cent of that from FS, however, Hurrell states there is also evidence from long-term feeding studies that suggests FF fortified cereals improve the iron status of infants.

Hurrell notes that the disparity between FF and FS on iron status is especially important in iron-deficient children.

However, he added that FF-fortified complementary foods have been shown to improve iron status in iron-deficient infants, and to prevent iron deficiency equally as well as ferrous sulphate in infants.

Recommendations​

Because iron deficiency is so common in infancy, the study recommends the lower rates of iron absorption from ferrous fumarate should be considered when defining fortification levels of infant foods.

Hurrell recommends the amount of iron added to infant foods should be “based on the amount of daily absorbable iron required from the food, the daily consumption of complementary food, and the expected bioavailability of the added iron.”​

The review states that a final recommendation on the use of ferrous fumarate in foods cannot presently be given due to a lack of research comparing iron absorption and efficacy from foods fortified with ferrous sulphate and ferrous fumarate in young children.

“Based on current evidence, it can be recommended that ferrous fumarate be added at the same iron concentration as ferrous sulphate in complementary foods designed to maintain iron status in largely iron replete infants, while it should be added at double or triple the iron level of ferrous sulphate if the target population is largely iron-deficient children,”​ wrote Hurrell.

Source: Nutrition Reviews​

Published online ahead of print, doi: 10.1111/j.1753-4887.2010.00312.x

"Use of ferrous fumarate to fortify foods for infants and young children”​

Author: R. Hurrell