Erythrocyte zinc and serum copper in male and female adolescents according to puberty stage at different growth phases

ABSTRACT

BACKGROUND: Considering that modification in body composition and growth velocity leads to alterations in zinc and copper nutritional status, the purpose of the study was to assess erythrocyte zinc and serum copper in adolescents of both genders, according to the stage of sexual maturity at different growth phases. METHODS: Two hundred and eighty-six adolescents were assessed, 157 were female, with body mass index Z-scorebetween−2 and +2. Clinical biochemical measurements were assessed using atomic absorption spectrophotometry. Student's t, Kruskal-Wallis, and Bonferroni tests were used. RESULTS Median serum copper was superior, and zinc was inferior to respective reference values in all groups. Serum copper presented significant reduction in the final stages of pubertal development in males; in turn, erythrocyte zinc values increased linearly with the evolution of puberty stages in both genders. Comparison between genders in each stage of growth showed significant difference in peak acceleration and in deceleration for erythrocyte zinc and serum copper, with both being higher in females. CONCLUSIONS: Serum copper is inversely influenced by modifications that occur with the evolution of puberty in males, whereas erythrocyte zinc is directly influenced in both genders, although always with deficient deposition. At peak acceleration and deceleration of growth, there is greater mobilization of erythrocyte zinc and serum copper in males, when compared with females, which does not occur at the onset of the acceleration of growth.