Calcium retention as a function of calcium intake in Asian adolescents

Thus, we investigated the relationship between calcium intake and calcium retention in Asian adolescents to define their calcium requirements based on our nonlinear model. Thirty healthy Chinese boys and girls, aged 12–15 years, who lived in the USA for more than 8 months, participated in two 3-week metabolic balance studies separated by a one week washout period. They were randomly assigned to paired calcium intake groups that covered a range of 600–1600 mg/day. A 4-day rotating menu provided 500 mg calcium per day. Varying levels of additional calcium were achieved with fortified orange juice. After a 1-wk equilibration period, calcium retention was calculated as calcium intake minus the calcium excreted in the feces and urine over the following 2 weeks. Calcium retention increased with calcium intake. Asian boys retained significantly more calcium than Asian girls (p<0.05). When compared to the values of Caucasian adolescents from our previous studies using a similar design, calcium retention was signi...