Submitted to: Meeting Abstract
Publication Type: Proceedings
Publication Acceptance Date: 10/1/1997
Publication Date: N/A
Interpretive Summary: This study was prompted by knowledge that zinc is necessary for growth and brain development, and a report that short stature (height) among Chinese children responded to treatment with zinc. Chinese first- and second- graders at risk for zinc deficiency received a daily treatment of 20 mg zinc alone, zinc plus micronutrients (a broad supplement based on U.S. RDAs sexcluding minerals that interfere with zinc absorption), or micronutrients alone for 10 wk. Nutritional status, growth and mental function were measured before and after treatment. Data collected before treatment indicated that the children were marginally deficient in zinc. Zinc status increased after treatment with micronutrients plus zinc and with micro- nutrients alone. The most improved growth also occurred after treatment with zinc plus micronutrients; micronutrients alone had an intermediate effect and zinc alone the least effect on growth. In contract, mental function showed the greatest improvement after treatment with zinc plus micronutrients and zinc alone. Thus zinc deficiency apparently is a problem among poor Chinese children, and repletion with zinc plus micro- nutrients seems to be the best treatment to improve zinc status, and thereby growth and mental function.
Technical Abstract: This report describes preliminary findings from a 10 week double-blind controlled trial of Zn repletion in 720 urban, low income children, aged 6 years, from Chongqing (CQ), Qingdao (QD) and Shanghai (SH), PRC. Treat- ments (Rx) were 20 mg Zn alone (Rx 1), 20 mg Zn with micronutrients (Rx2) and micronutrients alone (Rx 3). The micronutrient mixture was based on NAS/NRC guidelines. Nutrients that might interfere with Zn retention wer excluded or given in lower amounts. Main outcomes were changes in neuropsychological function and knee height. Hemoglobin, serum ferritin, plasma and hair Zn, and whole blood and hair lead (Pb) were also measured at baseline and follow-up. Anemia was not common, and serum ferritin concentrations were usually normal or increased. In CQ and QD baseline plasma Zn concentrations were marginal. Mean hair Zn concentrations were also marginal at baseline. At follow-up plasma Zn increased substantially y after Rx 2 and 3. Hair Zn decreased after all Rxs. Mean baseline whole blood Pb was slightly below the CDC cut-off for excess Pb in children. Inconsistent increases in blood Pb occurred after Rx 3. Maximal improve- ment in neuropsychological function occurred after the Zn-containing Rxs, but not after micronutrients alone. In contract, maximal growth occurred after the combination of Zn with micronutrients; micronutrients alone had an intermediate effect and Zn alone the least effect. Thus Zn deficiency apparently is a problem among poor Chinese children, and Zn plus micronutrient repletion will improve their growth and neuropsychological function.