Research On The Construction Of Breast Milk Fatty Acids Database And The Dietary Impact Of Breast Milk Fatty Acids

Objective: Breastfeeding is widely advocated worldwide for its beneficial effects on the healthy growth and development of infants.In addition to providing the energy needed for infant growth and development,the lipids in breast milk also participate in the regulation of a variety of cellular functions and play an important role in infant growth and development.The in-depth study on the composition and function of lipids in breast milk is the basis of the research on infant growth and development and developing formulas suitable for infant growth and development.At present,there is little research on the nutritional composition of breast milk in China,and the related basic research started late.Our study are about to initially establish a nationwide database of breast milk fatty acids by integrating published data and our own data.The purpose is to provide basic data for the research on the composition of breast milk fatty acids,the research on infant growth and development,and the development of infant formula.In addition,the relationship between dietary intake and the composition of fatty acids and phospholipids in breast milk was investigated to provide scientific guidance for lactating mothers to eat properly.Methods:(1)The data of the breast milk fatty acid database were derived from the research on breast milk fatty acids published in the past 15 years and the data collected by our study.The breast milk in the database was classified according to lactation period and regional economic level.The fatty acid composition and changing trend in different lactation periods were described,and the differences in fatty acid composition between regions with different economic levels were compared.(2)The mature milk of 147 mothers from Beijing,Guangdong,Sichuan and Jiangsu were collected,and their dietary intake in the last month was investigated using the dietary evaluation form.The contents of fatty acids in breast milk were determined by the normalization method in the national standard GB 5009.168-2016,and the contents and compositions of phospholipids in breast milk were determined by the using high performance liquid chromatography-mass spectrometry.SPSS 16.0 was used for data analysis,and the correlation analysis of the relationship between dietary intake and fatty acids and phospholipids in breast milk was conducted.If the variables were normally distributed,Pearson correlation analysis was used;if the variables were not normally distributed,Spearman correlation analysis was used.A two-tailed P < 0.05 was considered statistically significant.(3)The contents of fatty acids in infant formula milk powder(0-6 months old)of four different brands sold in China were determined by the normalization method in the national standard GB5009.168-2016,and the results were compared with the overall fatty acids contents in Chinese breast milk of the database we built.Results:(1)A total of 4727 cases of breast milk were included in the database,including 1327 cases of colostrum,900 cases of transitional milk,and 2,500 cases of mature milk.With the prolongation of the lactation period,the proportion of total saturated fatty acids(SFA)in breast milk has shown an increasing trend;The proportion of total monounsaturated fatty acids(MUFA)in breast milk showed a decreasing trend with the prolongation of lactation period,which decreased significantly during the transition milk period and then became stable;The proportion of total polyunsaturated fatty acids(PUFA)in breast milk increased first and then decreased with the prolongation of lactation period,and the changes of n-3 PUFA and n-6 PUFA were consistent with this trend.In the regions with better economic level,the content of SFA in mature milk was less,and the contents of MUFA and PUFA was higher than that of regions with low economic level,and the ratio of LA/ALA was slightly higher than the national standard.(2)In the mature milk of 147 lactating mothers,12 kinds of SFA,6 kinds of MUFA and 10 kinds of PUFA were detected.The total SFA content of breast milk in the four regions ranged from 34.46% to 37.04%,and there is no significant difference between regions;the total MUFA content ranged from 37.74% ～ 41.87%,which was significantly higher in Sichuan and Guangdong than in Jiangsu and Beijing;The content of total PUFA ranged from 22.71% to 27.26%,and the content in Sichuan and Guangdong was significantly lower than that in Jiangsu and Beijing.The total SFA content in breast milk was largely independent of dietary intake.The content of MUFA was positively correlated with the dietary intake of dairy products and vegetable oils.The content of PUFA was greatly affected by diet.The content of arachidonic acid(AA)was positively correlated with the intake of river fish.The content of Docosahexaenoic acid(DHA)was positively correlated with the intake of shrimp and crab.The content of phospholipids in human milk in China was 47 mg/100 m L,and the content of phosphatidylcholine(PC)and sphingomyelin(SM)was the largest,accounting for more than 60% of the total phospholipids.The content of phospholipids in breast milk was positively related to the intake of soy products and nuts.The composition of phospholipids was only affected by the intake of vegetable oils.(3)The contents of C16:0,C18:1 and Linoleic Acid(LA)in four infant formula milk powders sold in China accounted for more than 70% of the total fatty acids.The contents of all kinds of fatty acids are basically the same as that of breast milk,but the types of MUFA and PUFA were less than that of breast milkConclusion: This study initially established a database of breast milk fatty acids in China,which has basically presented the overall composition of Chinese breast milk fatty acids.Based on this,the composition characteristics of breast milk at different lactation periods and the differences between infant formula and breast milk fatty acids were compared,and the effects of economic level and dietary intake on the composition of fatty acids and phospholipids in breast milk were analyzed.These results provided basic data for the study of the composition of breast milk fatty acids,research on infant growth and development,the development of infant formula.and provided a reference for guiding the lactating mothers to a proper diet.