Serum iron, serum transferrin and transferrin saturation in healthy children without iron deficiency
Iron status was assessed by measurement of serum ferritin (S-ferritin), transferrin saturation and haemoglobin (Hb) in 270 healthy Faroese children (153 ♂, 117 ♀) 4, 8 and 13 years old. There were no significant differences between the three variables in boys and girls. Geometric mean S-ferritin increased from 16 μg/l in 4-year-old children to 21 μg/l in 8-year-old (P<0.01) and 25 μg/l in 13-year-old children (P<0.05). Likewise Hb displayed a gradual increase with age (P<0.001); the arithmetic mean Hb was 129 g/l in 4-year-old, 137 g/l in 8-year-old, and 143 g/l in 13-year-old children. Depleted iron stores (i.e. S-ferritin<12 μg/l) were present in 21.5% of 4-year-old, and in 12.7% of 8 and 13-year-old children. Latent iron deficiency (i.e. S-ferritin<10 μg/l and transferrin saturation<10%) was found in 3.1% of 4-year-old and in 0.5% of 8 to 13-year-old children. None of the children had iron deficiency anaemia. A high dietary intake of animal protein probably explains the low prevalence of iron deficiency.