Erythrocytic zinc content during childhood.

The aim of the study was to investigate developmental changes of erythrocytic zinc occurring during childhood. We have studied 166 healthy children (36 newborn infants, 34 infants aged 1-12 months, 15 aged 1-2 years, 15 children aged 2-4 years, 11 aged 4-6 years and 55 aged 6-12 years); 20 adults were also examined. Mean and standard deviations of the erythrocytic zinc content (pg/10(6) RBC) in the serial samples from children and adults were as follows: newborn infants: 507 +/- 197; infants aged 1-3 months: 521 +/- 117; aged 4-5 months: 559 +/- 203; aged 6-7 months: 574 +/- 251; aged 8-12 months: 771 +/- 243; aged 1-2 years: 802 +/- 204; aged 2-4 years: 963 +/- 278; aged 4-6 years 1,179 +/- 284; aged 6-12 years: 1,256 +/- 186; adults: 1,482 +/- 390. The results have shown that RBC zinc levels increase during the first years of life. Up to the 4th year it is still lower than that observed in adults, although after that age, the mean values do not vary significantly from those observed in adults.