514例乳母乳汁中AA和DHA水平及其影响因素分析

目的: 分析吉林省长春市乳母乳汁中花生四烯酸(AA)和二十二碳六烯酸(DHA)水平,探讨其影响因素。方法: 采用调查问卷的形式收集乳母基本信息,产后22~25 d收集乳母乳汁并应用"三天二十四小时膳食回顾法"对514名健康乳母进行膳食调查,采用《2009中国食物成分表》计算膳食中5种多不饱和脂肪酸(PUFAs)的摄入量,同时应用金钥匙营养专家系统软件计算乳母膳食中各类食物的摄入量。采用气相色谱法测定乳母乳汁中AA和DHA水平,采用线性回归模型分析影响乳母乳汁中AA和DHA水平的相关因素。结果: ①514例乳母乳汁中AA的平均浓度为(0.08±0.04)g·100g^-1,DHA平均浓度为(0.05±0.04)g·100g^-1。②单因素相关分析,膳食中油脂摄入量与乳母乳汁中AA和DHA水平呈正相关关系(r=0.360,r=0.354,P<0.001),而膳食中亚油酸(LA)、α-亚麻酸(ALA)、二十碳五烯酸(EPA)、DHA以及奶类制品和肉禽水产的摄入量与乳汁AA(r=-0.321,r=-0.280,r=-0.255,r=-0.299,r=-0.196,r=0.306,P<0.05)和DHA(r=-0.315,r=-0.279,r=-0.175,r=-0.189,r=-0.248,r=-0.142,P<0.05)水平均呈负相关关系。③线性回归分析,奶类及其制品(β=-0.265)和膳食EPA(β=-0.144)的摄入量与乳母乳汁中AA水平均呈负相关关系(P=0.009),而奶类及其制品的摄入量与乳母乳汁中DHA水平呈负相关关系(β=-0.233,P<0.001)。结论: 本研究对象群体中随奶类及其制品摄入量的增加,乳母乳汁中AA和DHA水平未见升高;且n-6系与n-3系多不饱和脂肪酸在代谢过程中存在竞争关系。

Analysis on levels of AA and DHA in breast milk and their influence factors of 514 lactating mothers

Objective:To analyze the levels of arachidonic acid (AA)and docosahexaenoic acid (DHA)in the breast milk of lactating mothers in Changchun City of Jilin Province, and to explore their influence factors. Methods:The lactating mother’s basic information was collected with questionnaire, and the breast milk of lactating mothers on postpartum 22-25 d was obtained and the 3-day 24-hour dietary recall method was used to investigate the dietary intake information of 514 healthy lactating mothers.The Food Composition Table of China 2009 was used to calculate the intakes of five kinds of polyunsaturated fatty acids (PUFAs) in diet of lactating mothers and the gold key nutrition expert system software for corresponding nutrient analysis was used to calculate the amount of various kinds of foods in the lactating mothers’daily diet.The levels of AA and DHA in breast milk were determined with gas chromatography and the linear regression was used to analyze the related factors of AA and DHA levels in breast milk.Results:①The average concentration of AA in breast milk of 514 lactating mothers was (0.08±0.04)g·100 g-1,and the average concentration of DHA was (0.05±0.04)g·100 g-1. ②The single factor correlation analysis results showed that the oil intake was both positively correlated with AA and DHA levels in milk of lactating mothers (r= 0.360,r=0.354,P<0.001),while the intakes of linoleic acid (LA), alpha linolenic acid (ALA),eicosapentaenoic acid (EPA),DHA,dairy and meats and seafood in diet were both negatively correlated with AA (r= -0.321,r=-0.280,r=-0.255,r=-0.299,r=-0.196 ,r=-0.306,P<0.05)and DHA (r=-0.315,r=-0.279,r=-0.175,r=-0.189,r=-0.248,r=-0.142,P<0.05).③The linear regression analysis results showed regression equation that dairy intake (β=-0.265)and EPA intake (β=-0.144)were both negatively correlated with the level of AA (P=0.009),and dairy intake was also negatively correlated with the level of DHA (β=-0.233,P<0.001).Conclusion:The AA and DHA levels in breast milk of lactating mothers didn’t increase with the increasing of intake of milk or dairy products in the study.Moreover there is a competitive relationship between n-6 and n-3 series polyunsaturated fatty acids in the process of metabolism.