Toward Precision Nutrition: Commercial Infant Formulas and Human Milk Compared for Stereospecific Distribution of Fatty Acids Using Metabolomics

Abstract

Precision nutrition and nutrimetabolomics are emerging omics technology applications in public health. In this context, the infant formula (IF) is a manufactured foodstuff that aims to match the composition of human milk (HM), especially the lipid profile. The IF manufacturers have achieved relative success in matching the predominant fatty acid (FAs) profiles, but the stereospecific structures of the triacylglycerides in HM require deeper analyses with system sciences. We employed NMR-based metabolomics to compare the lipid profiles of 12 commercial IF samples and 10 HM samples. Additionally, vegetables, fish, and microalgae oil as raw materials in IFs were also investigated to understand the lipid profile of IFs. We found that IF has significantly less saturated fatty acids (SFA), higher unsaturated FAs, and similar polyunsaturated fatty acid (PUFA) content, compared with HM. However, the main difference was the stereospecific distribution of FAs: HM samples were associated with a high content of SFAs in the sn-2 position (26.03% -2.93%) and PUFAs in the sn-1,3 position (15.35% -3.94%). The IF had the opposite distribution, with SFAs esterified mainly in the sn-1,3 position (33.07 -4.93%) and PUFAs in the sn-2 position (9.57% -7.05%). Consequently, the hydrolysis of HM results in SFA mainly as sn-2-monoacylglycerides, which are well absorbed. In contrast, the hydrolysis of the IF provided SFA, mainly as free FAs, which tend to bind calcium and form insoluble calcium soaps in the intestine. Taken together, these observations can inform optimal design of infant formulas with a view to precision nutrition.

A Comparison of Changes in the Fatty Acid Profile of Human Milk of Spanish Lactating Women during the First Month of Lactation Using Gas Chromatography-Mass Spectrometry. A Comparison with Infant Formulas

“…This is because some mothers cannot or choose not to breastfeed and 2 of 16 instead use infant formulas (IF) as a substitute. IF are manufactured foodstuffs for feeding newborns and babies that attempts to match, as much as possible, the composition of human milk (HM), especially the lipid profile [5]. Lipids are the largest source of energy in human milk.…”

Clinical insights gained through metabolomic analysis of human breast milk

“…c c e p t e d M a n u s c r i p t acid 82.7 mg/dL, glycine, and pyroglutamic acid 47.9 mg/dL), urea, and inositols (myo-inositol46.1mg/dL and scylloinositol). According to thesa data, metabolome of FM samples is highly different from BM and varies according to the kind of analyzed formula, while no significant differences occurred between first infant formulas and follow-up formulas[76].Lopes et al[77] focused the attention on lipid profile of BM vs FM, evaluating it with 1 H-NMR.N=12 commercial FM samples and n=10 BM samples from different mothers were compared. It was pointed out that FM shows a significantly lower content of saturated fatty acids (SFAs), higher content of unsaturated FAs (UFAs, 38.20% vs 30.59%) and a comparable polyunsaturated fatty acid (PUFA 9.92% vs 17.96%) level instead of BM.…”

“…On the contrary, FM showed SFAs esterified mainly in the sn-1,3 position (33.07 vs 4.93%) and PUFAs in the sn-2 position (9.57% vs 7.05%) instead of BM.Thus, both kind of samples show similar lipid profiles, but the most important difference was the stereospecific FAs distribution. Moreover, the levels of vegetables, fish, microalgae oil and raw materials were also measured in FM, to characterize in a better way its lipid composition[77].A comparative approach was used by Quian and co-workers[78], comparing BM metabolic profile to FM and bovine milk. Gas chromatography-time-of-flight mass spectrometry (GC-TOFMS) and ultra-performance liquid chromatography-quadrupole-time-of-flight mass spectrometry (UPLC-QTOFMS) were performed.…”

Current Practice in Untargeted Human Milk Metabolomics

“…The information regarding study design provided in HM metabolomics studies varies considerably [13][14][15][16][17][18][19][20][21][22][23][24][26][27][28][29][30][31][32][34][35][36][45][46][47] as shown in Figure 2. Repeatedly reported factors have been grouped into three categories and are discussed in detail in the following sections:…”

“…The analysis of the HM metabolome has been approached employing a variety of extraction and analytical techniques to respond to a spectrum of clinically relevant questions. Several studies have compared HM metabolome with formula milk [13,[16][17][18][19][20] or with milk from other mammalian species including monkey [21], donkey [17], and cow [18], whereas others have made efforts in defining the metabolome of preterm milk [13,16,[22][23][24][25][26] and the evaluation of the HM metabolome during the course of lactation [15,23,[27][28][29][30]. Furthermore, the influence of maternal diet [14,15,31], phenotype [14,32], obesity [30], or atopy status [33], as well as geographical location [33,34], time of the day [29,35], chemotherapy [36], or preeclampsia during pregnancy [31] on the HM metabolome have been reported.…”