The Effect Of High Sn-2 Palmitic Acid Infant Formula On The Absorption And Excretion Of Fatty Acids And Minerals In Infants

Objective:This study aimed to explore（1）the short-term effect of high sn-2 palmitic acid infant formula on the absorption and excretion of fatty acids and minerals in infants;（2）the potential long-term effects of high sn-2 palmitate infant formula through the study of infant defecation status and the dynamic detection of mineral and fatty acid content in fecal and serum of standard infant formula-fed,high sn-2 palmitate infant formula-fed and breast-fed infants.Methods:A prospective,randomized,double-blind study was used to research the healthy,term,singleton and gestational age infants born from June 2013 to December 2014.Nighty-four eligible infants were enrolled within 21days after birth.All the formula-fed participants were categorized into two groups according to the type of feeding:standard infant formula（IF）group and high sn-2 palmitic acid infant formula（HPIF）group.Breast-fed infants were also included in the study as control group（BF）.The anthropometric parameters and defecation status of infants were followed up to 90 days old.At the same time,the fatty acid profile and mineral content of feces,serum and milk samples were also detected.Results:（1）There was no significant difference of head circumference,body length and body weight among the three groups when these infants were born,at enrollment,on 42^nd day and 90^th day.（2）The defecation frequency of HPIF and IF two groups were both significantly lower than that of BF group on 42^nd day and 90^th day[42d:（5.5±3.2）,（5.2±3.3）and（10.2±7.2）times/d;90d:（4.9±3.0）,（4.5±2.0）and（6.7±5.3）times/d].The proportion of runny stool of formula-fed infants was significantly lower than BF group[42d:14.2%,8.2%and 50.4%;90d:15.8%,10.8%and 55.0%],but the proportion of formed stool of formula-fed infants was significantly higher than BF group[42d:47.6%,53.8%and 4.7%;90d:40.7%,46.0%and 4.9%].There was no significant difference between HPIF group and IF group in defecation frequency and stool traits.（3）The fecal calcium content of HPIF and IF two groups were significantly higher than that of BF group at 42^nd day[（38.3±14.0）,（38.8±15.5）and（21.3±13.7）mg/g dry feces]（P<0.05）.The fecal calcium content of HPIF group was significantly lower than that in IF group at 90^thh day[（31.1±11.2）and（45.9±16.5）mg/g dry stool]（P<0.05）,but still significantly higher than BF group[（31.1±11.2）and（21.5±9.9）mg/g dry stool]（P<0.05）.The contents of magnesium in feces of HPIF and IF two groups were both significantly higher than that of BF group at 42^nd day and90^th day.There was no difference between HPIF group and IF group[42d:（3.5±1.4）and（3.8±1.7）mg/g dry stool,90d:（4.0±2.1）和（4.2±1.5）mg/g dry stool].（4）The content of palmitic acid in feces of HPIF and IF two groups were significantly higher than BF group at 42^nd day[（31.1±9.8）,（30.9±10.7）and（10.8±8.8）mg/g dry feces]（P<0.05）.The content of palmitic acid in feces of HPIF group was significantly lower than that in IF group at 90^th day[（24.3±9.8）and（29.9±7.9）mg/mg dry feces]（P<0.05）,while the HPIF group was significantly higher than that in BF group[（8.9±8.4）mg/g dry feces]（P<0.05）.（5）The fecal calcium content in three groups of infants was significantly correlated with the content of palmitic acid in faces（r=0.909,P<0.05）.（6）At the age of 90 days,the concentration of total free long-chain fatty acid,palmitic acid and stearic acid in serum of HPIF group were significantly higher than that of both IF group and BF group.The serum concentration of total unsaturated long-chain free fatty acid,palmitoleic acid,oleic acid and linoleic acid in HPIF group were significantly higher than that of IF group and BF group.There were no differences between the latter two groups.（7）No significant difference showed among the serum calcium content of three groups[（123.4±24.3）,（114.9±37.6）and（125.0±19.8）mg/l]（P>0.05）.There was no significant difference of serum magnesium content among three groups.Conclusions:Compared with standard infant formula,feeding with high sn-2 palmitic acid infant formula can reduce the level of fecal calcium excretion,even makes it closer to the level of breast-fed infants.At the meantime,high sn-2 palmitic acid infant formula could significantly reduce the loss of palmitic acid in feces and increase the serum concentration.There is no short-term effect of high sn-2 palmitic acid infant formula on infants’growth.But the long-term effects of high sn-2 palmitic acid formula milk feeding on infants still need long-term follow-up.Breast milk is still the first choice for infants.