Development of iron status and response to iron medication in pubertal boys

During male puberty, rapid growth of body mass and the rise in hemoglobin concentration require much iron. The increasing need for iron may carry a risk of iron deficiency. Criteria for iron deficiency in adolescence are difficult to assess, as indicated by prevalences ranging from 0.5 to 30% in five recent studies from developed countries. We followed 60 prepubertal or early pubertal boys, testing them at 6-month intervals for 24 months and relating hemoglobin levels and other iron parameters to age, pubertal development, and response to iron medication. A significant increase in mean hemoglobin was first seen at genital stage G4. In early puberty, in contrast, between stages G1 and G3, ferritin decreased. Mean transferrin increased slightly during the study. The prevalence of iron deficiency increased both with age and with advancing puberty. However, the early decline in ferritin may be a physiologic response to guarantee increasing intestinal absorption. After iron medication, we observed improvements in the levels of our parameters of iron status, which showed that hemoglobin levels had been limited by iron deficiency. In pubertal boys, evaluation of iron deficiency should not be based on laboratory parameters alone; age, pubertal development, and growth should also be taken into account.