title: [Influence of hormonal contraceptives on indices of zinc homeostasis and bone remodeling in young adult women].
abstract: OBJECTIVE
  To investigate the influence of the use of oral hormonal contraceptive agents (OCA) on the biochemical indices related to metabolic zinc utilization and distribution, and to bone turnover in young adult women.
  
  
  METHODS
  Cross-sectional study. Blood and urine samples from non-users (-OCA; control; n=69) and users of hormonal contraceptives for at least 3 months (+OCA; n=62) were collected under controlled conditions. Indices of zinc homeostasis and of bone turnover were analyzed in serum or plasma (total, albumin-bound and α2-macroglobulin-bound zinc, albumin and total and bone alkaline phosphatase activity), in erythrocytes (zinc and metallothionein) and in urine (zinc, calcium and hydroxyproline). The habitual zinc and calcium intakes were evaluated by a food frequency questionnaire.
  
  
  RESULTS
  Dietary zinc intake was similar in both groups and on average above recommended values, whereas calcium intake was similarly sub-adequate in +OCA and -OCA. Compared to controls, +OCA had lower concentrations of total and α2-macroglobulin-bound zinc (11 and 28.5%, respectively, p<0.001), serum albumin (13%, p<0.01), total and bone-specific alkaline phosphatase activity (13 and 18%, respectively, p<0.05), erythrocyte metallothionein (13%, p<0.01), and, urinary zinc (34%, p<0.05).
  
  
  CONCLUSIONS
  OCA use decreases serum zinc, alters zinc distribution in major serum fractions with possible effects on tissue uptake, enhances zinc retention in the body and decreases bone turnover. Prolonged OCA use may lead to lower peak bone mass and/or to impaired bone mass maintenance in young women, particularly in those with marginal calcium intake. The observed OCA effects were more evident in women younger than 25 years and in nulliparous women, deserving special attention in future studies.
authors: Departamento de Química do Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, BR.
authors: Tania Mara Rodrigues
authors: TM
authors: Simões
authors: Facultad de Ciencias Básicas, Universidad del Atlántico, Barranquilla, CO.
authors: Carmiña Lucía Vargas
authors: CL
authors: Zapata
authors: Departamento de Química do Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, BR.
authors: Carmen Marino
authors: CM
authors: Donangelo
mesh_terms: D000328:Adult; D016723:Bone Remodeling / Q000187:drug effects*; D003270:Contraceptive Agents; D003278:Contraceptives, Oral, Hormonal / Q000494:pharmacology*; D003430:Cross-Sectional Studies; D005260:Female; D006706:Homeostasis / Q000187:drug effects*; D006801:Humans; D055815:Young Adult; D015032:Zinc / Q000502:physiology*
chemical_list: D003270:Contraceptive Agents; D003278:Contraceptives, Oral, Hormonal; D015032:Zinc