Iron fortified follow on formula from 9 to 18 months improves iron status but not development or growth: a randomised trial

AIMS Iron deficiency anaemia is associated, in observational studies, with developmental disadvantage. This study tested the hypothesis that feeding iron supplemented formula from 9 to 18 months of age would improve developmental performance. SUBJECTS AND METHODS 493 healthy children aged 9 months being fed pasteurised cows’ milk were recruited from three UK centres. They were randomised to: cows’ milk as before, formula containing 0.9 mg/litre iron, or formula containing 1.2 mg/litre iron, until 18 months of age. Bayley mental and psychomotor developmental indices were measured at 18 months, as were growth and haematological indices. RESULTS Children fed iron fortified formula had higher plasma ferritin concentrations, but there were no significant intergroup differences in development or growth. CONCLUSIONS There are no developmental or growth advantages in children given iron supplemented formula, but a benefit for a minority who were anaemic, or the possibility that a benefit may emerge at a later age, cannot be excluded.