Effects of Term Infant Formulas Containing High sn‐2 Palmitate With and Without Oligofructose on Stool Composition, Stool Characteristics, and Bifidogenicity

Abstract

Objectives:Levels of stool fatty acid soaps and beneficial bacteria differ between formula-fed and breast-fed infants; addition of specific formula ingredients may reduce these differences. This study evaluated the effects of a term infant formula containing high sn-2 palmitate term infant formula (sn-2) or an identical formula supplemented with oligofructose (OF) at 2 concentrations (sn-2+3 g/L OF, sn-2+5 g/L OF) on stool composition, stool characteristics, and fecal bifidobacteria.Methods:Healthy, term formula-fed infants 7 to 14 days old (n = 300) were randomized in a double-blind manner to receive standard formula (control), sn-2, sn-2+3 g/L OF, or sn-2+5 g/L OF for 8 weeks. Human milk (HM)–fed infants (n = 75) were studied in parallel. Stool samples were collected from all subjects at week 8 for fatty acid soaps and mineral content, and from a subset at baseline and week 8 for bifidobacteria. Stool characteristics were assessed via 3-day diary.Results:The sn-2 group had 46% less stool soap palmitate (P < 0.001) and softer stools than control (20% more mushy soft stools, P = 0.026; 50% fewer formed stools, P = 0.003). Addition of OF resulted in even fewer formed stools versus control (65% fewer for sn-2+3 g/L OF, 79% fewer for sn-2+5 g/L OF), with 5 g/L OF more closely resembling that of HM-fed infants. Both sn-2 (P < 0.05) and sn-2 with OF groups (P < 0.01) had significantly higher fecal bifidobacteria concentrations than control at week 8, not differing from HM-fed infants.Conclusions:High sn-2-palmitate formulas led to reduced stool soaps, softer stools, and increased bifidobacteria, whereas addition of OF further improved stool consistency. Those modifications brought outcomes in formula-fed infants closer to that in HM-fed infants.

Characterisation of Fecal Soap Fatty Acids, Calcium Contents, Bacterial Community and Short-Chain Fatty Acids in Sprague Dawley Rats Fed with Different sn-2 Palmitic Triacylglycerols Diets

“…However, we did not discriminate between calcium in soaps and “non-soaps”, because of the experimental challenge due to the poor solubility of the soap complex in organic solvents [22] to prove this assumption. Nevertheless, in the present study, fecal calcium was used to estimate the calcium absorption in the rat fed different sn -2 PA diets as previously reported in other studies [17, 23] and our results indicate a positive correlation between dietary sn -2 PA level and calcium absorption. This observation is in agreement with the finding by previous reports [1, 28], in which the authors found that fecal calcium excretion of preterm infants fed high sn -2 PA formula was significantly lower compared with infants fed low sn -2 PA formula.…”

“…But little is known if the structure of triacylglycerols is important for altering the intestinal microbiota composition. Although previous studies demonstrated that high percentage of sn -2 PA structured triacylglycerols in infant formula promoted beneficial gut microbiota, such as Lactobacillus and Bifidobacterium , in stool compared with low percentage of sn -2 PA structured triacylglycerols using a culture-dependent technique [16] and fluorescent in situ hybridization (FISH) technique [17]. However, the conclusions are not representative for most bacterial species in the gut.…”

Scientific Opinion on the essential composition of infant and follow-on formulae

“…In addition, no cause and effect relationship could be established by the Panel previously between the feeding of formula high in sn-2 palmitate and stool consistency (EFSA NDA Panel, 2014d). The study by Yao et al (2014), which was published after the opinion of the Panel, reported a significantly higher percentage of mushy soft stools and a significantly lower percentage of formed stools in the group consuming formula high in sn-2 palmitate than in controls. However, results from the pre-planned analyses on the average stool consistency scores between groups and on the percentage of stools in the other stool consistency categories (in total five) were not reported.…”

Tolerance and Efficacy of Infant Formula with High Sn-2 Palmitate in Formula-Fed Chinese Term Infants: an Open Label, Controlled Trial

“…However, compared with breastfed infants, the FF group stool in the early 3 months of life was less soft (ClinicalTrials.gov Identifier: NCT01157390). sn-2 palmitate, such as increasing beneficial gut flora [15,16] and reducing infant crying [17]. According to our knowledge, this is the first study examining an infant formula with milk fat, prebiotics and structured lipids.…”

“…Moreover, it was demonstrated in both preterm and term infants that by increasing the proportion of sn-2 position palmitate in the formula not only that the excretion of palmitate and associated calcium soaps in the stool is reduced and calcium absorption subsequently increased, but also stool hardness is reduced [14]. During the last years, the importance of a fat structure which is similar to that of human milk fat, was further revealed by additional benefits known for human milk, that were demonstrated for infant formula with high sn-2 palmitate, such as increasing beneficial gut flora [15,16] and reducing infant crying [17]. According to our knowledge, this is the first study examining an infant formula with milk fat, prebiotics and structured lipids.…”