中国成人硒需要量研究

STUDY ON THE SELENIUM REQUIREMENT FOR CHINESE

目的探讨使人体血浆硒蛋白P(SEPP1)达到饱和的硒摄入量,以评估硒需要量,为膳食硒参考摄入量DRIs的修订提供参考。方法对98名低硒健康受试者(体重平均58kg)进行为期40w的双盲补硒实验。随机分为七组,补硒(以硒蛋氨酸形式)剂量分别为0、21、35、55、79、102和125μg/d。定期检测血浆中谷胱甘肽过氧化物酶(GPX3)活性、SEPP1含量和硒含量等硒状态功能指标。选择剂量响应曲线的饱和平台起始点的相应摄入量作为该指标的需要量。结果在实验40w时,使血浆SEPP1含量达到饱和的硒摄入量为49μg/d;使血浆GPX3活性达到饱和的硒摄入量为35μg/d;血浆硒不能达到饱和平台,故不能用来作为评价硒需要量的指标。结论就当前人体实验而言,血浆SEPP1含量是反映硒营养状态和测定硒需要量的最佳指标。所以,满足SEPP1合成的硒摄入量49μg/d,经体重和个体变异等因素适当调节后,可作为人体硒需要量和修订膳食硒参考摄入量DRIs的参考。

Objective To determine the intake of selenium needed to optimize human plasma selenoprotein P（SEPP1）,thus allowing estimation of the selenium requirement.The value could be used as a reference for revising human selenium DRIs.Method A placebo-controlled double-blind study of selenium supplementation for 40 w was carried out in 98 healthy subjects（58kg bw） with low selenium status.Seven groups were assigned randomly with daily dose of 0,21,35,55,79,102,and 125 g selenium as selenomethionine.Plasma glutathione peroxidase（GPX3） activity,SEPP1 concentration,and selenium concentration as biomarkers were determined at intervals.A biomarker was considered optimized when its mean value was at the starting-point of plateau of dose-response curve.This corresponding intake could be assigned as selenium requirement.Results SEPP1 concentration was optimized at 40 w by selenium intake of 49 ？g/d.GPX3 activity was optimized by selenium intake of 35 ？g/d.Selenium concentration did not become saturated,thus it couldn＇t be used as biomarker to estimate the selenium requirement.Conclusion Plasma SEPP1 concentration is the best biomarker of selenium nutritional status and used for estimating selenium requirement.The selenium intake of 49 g/d with appropriate adjustments for body weight and individual variation can be used to estimate the human selenium requirement and as a reference for revising human selenium