Iron status of French-Canadian children: a three year follow-up study

Dietary iron intake and hematocrit, hemoglobin, serum iron, transferrin saturation and serum ferritin were studied longitudinally in 425 French-Canadian children from upper-middle class families at 3, 6, 9, 12, 15, 18, 24 and 36 months. At 3 to 9 months, the median iron intake exceeded the amount recommended (7 mg/d), at 12 to 36 months it was close to the amount recommended (8 mg). The proportion of anaemic children as diagnosed by low hematocrit and hemoglobin values did not exceed 5 percent except at three months of age. Transferrin saturation lower than 16 percent was detected in 12 percent of the children aged 12-18 months and 8 percent of those aged 24-36 months. Serum ferritin increased from 18 to 36 months of age; between 18 months and 3 years, the proportion of children with deficient serum ferritin (SF less than 10 ng/ml) and low iron reserves (SF 10-20 ng/ml) declined respectively from 29 to 2 percent and 55 to 26 percent. Thus, as the children grew older the iron intake still permitted the improvement of hematologic parameters of iron status in most subjects. The progressive increase of hematological values with age emphasizes the need for more specific standards for children of various ages.