A longitudinal study of serum ferritin in 319 adolescent Danish boys and girls examined in 1986 and 1992

This study examined trends in iron status in adolescents. Serum ferritin wa s measured in 1986 and 1992 in 319 Danes (161 males) stratified into 5 grou ps: I. median age 9 yr in 1986 vs. 15 yr in 1992; II. 11 vs. 17 yr; III. 13 vs. 19 yr; IV. 15 vs. 21 yr; V. 17 vs. 23 yr. Males in group I demonstrate d no change in ferritin or estimated iron stores in mg/kg; groups II-V disp layed an increase in iron status parameters. All groups showed an increase in estimated total iron stores. Changes in iron status parameters were inve rsely correlated with height velocity in group III, and positively correlat ed with height velocity in group V. Females in age groups I and II demonstr ated a fall in ferritin and estimated iron stores in mg/kg in association w ith menarche; values were unchanged in groups III and IV, and increased in group V. All groups showed an increase in estimated total iron stores. Chan ges in iron status parameters were inversely correlated with height velocit y in groups I and II. In conclusion, ferritin levels in adolescents display great variation during growth spurt and at menarche. Changes in ferritin s howed no consistent association with growth velocity. In both genders, esti mated total iron stores increased with age.