Zinc Absorption from Representative Diet in a Chinese Elderly Population Using Stable Isotope Technique

Objective To determine the dietary zinc absorption in a Chinese elderly population and provide the basic data for the setting of zinc （Zn） recommended nutrient intakes （RNI） for Chinese elderly people. Methods A total of 24 elderly people were recruited for this study and were administered oral doses of 3 mg 67Zn and 1.2 mg dysprosium on the fourth day. The primary macronutrients, energy, and phytic acid in the representative diet were examined based on the Chinese National Standard Methods. Fecal samples were collected during the experimenta and dysprosium content. period and analyzed for zinc content, 67Zn isotope ratio, Results The mean （± SD） zinc intake from the representative Chinese diet was 10.6 ± 1.5 mg/d. The phytic acid-to-zinc molar ratio in the diet was 6.4. The absorption rate of 67Zn was 27.9% ±9.2%. The RNI of zinc, which were calculated by the absorption rate in elderly men and women, were 10.4 and 9.2 mg/d, respectively. Conclusion This study got the dietary Zn absorption in a Chinese elderly population. We found that Zn absorption was higher in elderly men than in elderly women. The current RNI in elderly female is lower than our finding, which indicates that more attention is needed regarding elderly females＇ zinc status and health.