Lack of iron has lasting effects

Breast milk is a source of iron

Having an iron deficiency affects a child's development, even if they are given supplements, researchers claim.

University of Michigan scientists found infants who had low iron levels lagged behind healthy peers, even as teenagers.

This was despite the fact they had all been treated for their condition.

The researchers told the US Pediatric Academic Societies meeting their study showed it was important to prevent iron deficiencies in infants.

Iron deficiency does have an effect on cognitive function in young children and this study suggests that this may not be fully reversible Amanda Wynne, British Dietetic Association

Iron-deficiency anaemia affects about a quarter of infants across the world. Twice as many have iron deficiency without anaemia.

Iron - which babies get from their mothers during pregnancy, then from breast milk and foods such as dried fruit and fortified cereals - is crucial in the development of a child's brain.

Symptoms of iron deficiency include fatigue, poor appetite, delayed mental development in young children and increased risk of infection.

Widening gap

Researchers monitored Costa Rican children who had been diagnosed as being iron-deficient and treated with iron supplements when they were aged one to two-years-old.

Altogether, 191 children in working- to middle-class families were studied. Those who were diagnosed with an iron deficiency were treated with iron supplements.

Researchers assessed their motor skills and learning and understanding as infants, at age five, 11-14 and again at 15-17.

But there was no evidence that treatment allowed iron deficient children to "catch up".

Instead, the gap seemed to widen over time.

Children who had previously suffered iron deficiency scored around six points lower on cognitive tests at age one to two, and 11 points lower at age 15-18.

The gap was widest for children of families with low socioeconomic status, lower levels of stimulation in the home and for children whose mothers had lower IQs.

Those who had better family conditions generally scored lower than healthy children in initial tests, but their performance did not get any worse.

In children who had not had an iron deficiency, those who had scored higher on early tests tended to do less well over time, while those who did less well improved.

Family background did not appear to affect the cognitive test scores of children who had had good iron levels as infants.

UK research

Dr Betsy Lozoff, an expert in iron deficiency who led the research said: "It looks like good iron status helps buffers a bad environment, but chronic, severe iron deficiency, combined with poor family conditions, really hurts children's test performance."

She said her findings showed it was crucial to prevent children from developing iron deficiencies at all.

Amanda Wynne of the British Dietetic Association told BBC News Online: "We need to remember that there are many factors that affect cognitive function, including socio-economic group, stimulation in the home, and IQ.

"However, iron deficiency does have an effect on cognitive function in young children and this study suggests that this may not be fully reversible."

She added: "More research is needed to confirm these results, particularly looking at the effects on children here in the UK."