Selenium intakes, absorption, retention, and status in adolescent girls

Objectives: To assess selenium intakes, absorption, retention, and status in healthy adolescent girls and the effect of calcium supplementation on selenium parameters. Design: Annual 2-week study conducted each year for 3 consecutive years in which yearly selenium intakes, absorption, and retention and blood selenium status were measured. Setting: A metabolic unit in a large metropolitan hospital located in Columbus, Ohio - a low selenium region of the United States. Subjects Healthy white girls aged 11 to 14 years (n=16) enrolled in a calcium balance study and randomly assigned to receive a placebo of methylcellulose (n=9) or a calcium supplement containing 1,000 mg supplemental calcium as calcium citrate malate (n=7). Interventions Each subject consumed a diet with ∼100 μg selenium/day during the yearly 2-week balance studies. Results Selenium status measurements (serum and erythrocyte selenium and glutathione peroxidase activity) were all within normal ranges for adults during the study. Apparent selenium absorption averaged 71%, 76%, and 74% for years 1,2, and 3 of the study, respectively, and did not vary significantly (P>.05). Average daily selenium retention did not differ among the years of the study (P>.05) and indicated that the usual selenium intake was ∼100 μg daily. Measurements of selenium status and retention did not differ between calcium-supplemented and placebo groups. Conclusions An intake of ∼100 μg selenium/day is the typical intake of the mineral among the subjects and appeared adequate to maintain selenium status in these healthy adolescent girls; in addition, calcium supplementation of 1,000 mg daily does not have a negative impact on selenium parameters.