Breast milk nutrient content and infancy growth

Global levels and variations of breast milk fatty acids and triacylglycerols: A systematic review and meta-analysis

Understanding global temporal and spatial variations in breast milk composition is crucial for developing personalized infant nutrition strategies. This study analyzed 46,673 breast milk samples from 171 studies using a random-effects model to evaluate total fatty acids (TFA), sn-2 fatty acids (sn-2 FA), and triacylglycerols (TAG) across lactation stages, regions, and sample years. Results showed that saturated fatty acids (SFA) increased while unsaturated fatty acids (UFA) decreased with prolonged lactation, with corresponding changes in triacylglycerol profiles. Geographically, Africa had the highest SFA and lowest UFA, Asia had the highest PUFA, and Europe had the highest MUFA. Over time, SFA and SFA-dominant TAGs declined, while UFA and UFA-dominant TAGs rose. These variations reflect shifts in maternal diet, infant nutritional needs, and potential growth outcomes, highlighting the importance of monitoring breast milk lipids to optimize infant nutrition strategies.

Global Levels and Variations of Cholesterol and Polar Lipids of Human Milk: A Systematic Review and Meta-analysis

Polar lipids and cholesterol are vital structural components of the milk fat globule membrane, playing a crucial role in infant growth and development; however, systematic global reports on their content in human milk are currently lacking. This study conducted a systematic literature search in Chinese and English databases, including 69,392 human milk samples from 96 studies. A random-effects model based on global data was used to assess the content of total lipids, cholesterol, gangliosides, and phospholipids in human milk and their variations with the lactation stage, geographical region, and sample year. The mean contents of total lipids, cholesterol, and total phospholipids were 2774.15 mg/100 g (95% CI: 2614.88, 2933.42 mg/100 g), 21.15 mg/100 g (18.35, 23.95 mg/100 g), and 70.72 mg/100 g (68.84, 72.60 mg/100 g), respectively, with gangliosides GM3 and GD3 at 0.63 mg/100 g (0.54, 0.72 mg/100 g) and 0.34 mg/100 g (0.32, 0.36 mg/100 g). The major phospholipids SM, PC, PE, PS, and PI averaged 24.19 mg/100 g (23.17 and 25.21 mg/100 g), 21.27 mg/100 g (19.92 and 22.62 mg/100 g), 18.28 mg/100 g (17.46 and 19.10 mg/100 g), 2.86 mg/100 g (2.32 and 3.40 mg/100 g), and 2.12 mg/100 g (1.75 and 2.49 mg/100 g). With the progression of lactation, total lipids, gangliosides, and most phospholipids (SM, PC, PS, PI) increased, while cholesterol and PE decreased. Over the years, total lipids, gangliosides, and PE showed an upward trend, whereas cholesterol and most phospholipids declined. Human milk from Europe had lower total lipid and cholesterol levels compared with other regions. While the total phospholipid content did not show significant regional differences (P > 0.05), variations in phospholipid composition were observed. These findings emphasize the importance of understanding spatiotemporal changes in human milk lipids to develop personalized nutrition strategies that support optimal infant growth and development.

Maternal obesity, age and infant sex influence the profiles of amino acids, energetic metabolites, sugars, and fatty acids in human milk

PURPOSE

This study aimed to evaluate whether maternal nutritional status, maternal age, mode of delivery, and the infant's sex influence the profiles of amino acids, energetic metabolites, sugars, and fatty acids and as well as the metabolic pathways in mature human milk human milk (HM).

METHODS

This was a cross-sectional, prospective, and observational study. HM samples from normal weight (NW, n = 60), overweight (OW, n = 35), and obese (OB, n = 14) women were analyzed using a non-targeted GC-MS method to identify the metabolome. Data obtained were analyzed with Metaboanalyst software (v. 5.0) and SPSS (v.25.0).

RESULTS

OB women HM contains a higher proportion of amino acids such as leucine, lysine, tyrosine, and aspartic acid, energy metabolites such as lactic and succinic acid, and sugars and derivatives such as fucose, rhamnose, and gluconic acid (p < 0.05) compared with normal weight women HM. HM from women > 25 years of age contains a lower proportion of lauric acid and a higher proportion of leucine and tyrosine (p < 0.05) than ≤ 25 years women HM. Also, HM intended for female infants has a higher leucine and gluconic acid content. The main altered metabolic pathways in OB women HM correspond to amino acids and energetic metabolism.

CONCLUSION

OB women HM provides more amino acids, energetic molecules, and sugars. Increased maternal weight, BMI, and body fat mass predispose to more leucine and aspartic acid in HM. Maternal age influences lauric acid, leucin, and tyrosine levels, while the infant's sex influences leucine and gluconic acid levels in HM. The impact of obese women's HM metabolome on the offspring's physiology needs to be explored.

TRIAL REGISTRATION

R-2021-785-096.

Maternal Phenotype, Infant Size and Breast Milk Composition in Women Living With HIV

The impact of maternal factors on the size of HIV-exposed-uninfected (HEU) infants and breast milk composition is poorly understood. Anthropometry, bio-electrical impedance, haemoglobin and HIV viral load data of women living with HIV (WLWH) and without HIV (WLWOH) were compared and related to their infants' anthropometric Z-scores and breast milk macronutrients 6 weeks and 6 months postnatally. At both time points, WLWH (6-week: n = 83; 6-month: n = 63) had lower reactance (measure of body cell mass) (6-week: p = 0.016; 6-month: p < 0.001), phase angle (PhA) (measure of cell health) (6-week: p = 0.001; 6-month: p = 0.002) and haemoglobin (6-week: p = 0.002; 6-month: p = 0.004) than WLWOH (6-week: n = 90; 6-month: n = 73). HEU infants had lower weight-for-age Z-scores (WAZ) (6-week: p = 0.010; 6-month: p = 0.005). Breast milk composition did not differ between groups. At 6 weeks, HEU infants had lower head circumference-for-age Z-scores (HCAZ) (p = 0.014). Bivariate regression demonstrated maternal HIV predicted lower infant WAZ (ß = -0.442; p = 0.011) and HCAZ (ß = -0.445; p = 0.014). Maternal body mass index (BMI) and mid-upper arm circumference were positively associated with breast milk protein content (ß = 0.018; p = 0.014 and ß = 0.025; p = 0.002, respectively). At 6 months (bivariate regression) maternal HIV predicted lower infant WAZ (ß = -0.609; p = 0.005) and length-for-age Z-scores (ß = -0.741; p = 0.018). Higher maternal BMI and PhA were associated with higher infant WAZ (ß = 0.622; p = 0.015 and ß = 0.055; p = 0.017, respectively). On multivariable analysis, maternal HIV remained a predictor of lower WAZ (ß = -0.568; p = 0.024). In conclusion, maternal HIV infection and phenotype predict the size of infants and breast milk composition up to 6 months postnatally.

Breast Milk Macronutrient Content and Its Effects on Infant Anthropometric Measurements in the First 6 Months: A Systematic Review and Meta-Analysis

PURPOSE

The aim of the study is to determine the effect of the macronutrient content of breast milk on the anthropometric measurements of infants in the first 6 months.

BACKGROUND

Breast milk contains essential macro- and micronutrients needed in the early stages of an infant's development. Current literature highlights the importance of understanding how breast milk's macronutrient content influences infant growth.

METHODS

The study protocol has been published in PROSPERO (CRD42023425550). This study adheres to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guideline. Studies published between January 1, 2016, and June 2, 2023, were reviewed across 6 databases. The Joanna Briggs Institute Cohort Studies checklist was used to assess methodological quality. Effect sizes were calculated using both fixed-effects and random-effects models.

RESULTS

Six studies were included in the systematic review and meta-analysis. The meta-analysis indicated a significant relationship between lactose content in breast milk and infant weight gain, length growth, and head circumference, as well as between fat-lipid content and infant weight gain within the first 6 months (P < .05). No significant relationship was found between protein or carbohydrate content of milk and anthropometric measurements of infants in the first 6 months (P > .05).

CONCLUSION AND IMPLICATIONS

The findings suggest that macronutrient concentrations in breast milk are important determinants of infant growth. Further research with high level of evidence and standard methodological protocols is recommended to elucidate the relationships between breast milk content and infant growth.

Exclusive or partial breastfeeding and estimated protein intake in infancy: Associations with childhood growth and body composition at 7 years of age in the Odense Child Cohort

BACKGROUND

Protein intake in infancy influences infant growth, body composition, and possibly metabolic programming later in life. Our objectives were to investigate whether macronutrient content in mother's own milk (MOM) differed between exclusive (EBF) or partial breastfeeding (PBF), including an estimation of protein intake (ePI) during the first 6 months of life. Second, to investigate associations of feeding type and ePI with childhood growth and body composition at 7 years.

METHODS

In a subset of 150 participants from the Odense Child Cohort, MOM was analysed for macronutrient content using midinfrared transmission spectroscopy. Information on breastfeeding duration was collected through weekly SMS questionnaires and used to calculate ePI. Outcomes were weight-for-age z-scores (WAZ) and height-for-age z-scores (HAZ) from birth to 7 years, and body composition in terms of dual X-ray absorptiometry fat mass, fat-free mass and calculated indexes at 7 years.

RESULTS

The macronutrient content in MOM did not differ between EBF and PBF, but ePI was significantly higher in PBF infants than in EBF infants at 6 months. We found no difference in WAZ or HAZ until 7 years of age according to feeding type, but within the PBF group, ePI was positively associated with 7-year WAZ (β = 0.001; 95% CI 0.000-0.003; p = 0.03) and HAZ (β = 0.002; 0.001-0.003;p = 0.007). ePI was not associated with body composition at 7 years.

CONCLUSION

Milk macronutrient content and childhood growth did not differ between EBF and PBF during infancy. Estimated protein intake in partially breastfed infants was positively associated with childhood growth, but not body composition, at 7 years of age.

Composition of linear and branched short-chain fatty acids in human milk and newborn feces: influence of perinatal and maternal factors

This research aimed to analyze the percentage of short-chain fatty acids (SCFAs) in human milk (HM) and newborn feces and to explore potential associations with factors such as maternal nutrition, age, biological sex, delivery mode, diet, and the type of HM. Gas chromatography was used to measure the percentage of SCFAs in colostrum (n = 23), transitional HM (n = 23), and mature HM (n = 92) and feces of newborn (n = 36) at day 30 postpartum. Anthropometry was also evaluated in the mother and the infant. The results showed that acetic acid was the most abundant in HM. The percentage of butyric acid and isovaleric acid was higher (p < 0.05) in the feces of newborns whose mothers were overweight/obese or were male, respectively, compared to newborns whose mothers were of normal weight or were female. The percentage of valeric acid was higher in the feces of newborns whose mothers were over 30 years old and who were delivered by C-section, compared to newborns whose mothers were 30 years old or younger and who were delivered vaginally. Inadequate intake of proteins, carbohydrates, and fiber was associated (p < 0.05) with lower acetic acid and higher butyric acid, higher propionic acid and lower butyric acid, and higher isovaleric acid percentage, respectively, in mature HM. The percentage of acetic acid was higher (p < 0.01) and that of propionic acid, butyric acid, isobutyric acid, and isovaleric acid was lower (p < 0.01) in colostrum compared to mature HM. The intake of lipids was associated with the percentage of butyric acid (β = -0.32, p = 0.01), and the percentage of propionic acid (β = 0.43, p < 0.01) was associated with carbohydrate intake. Overall, this study concluded that factors such as maternal nutritional status, diet, age, biological sex, and delivery mode were related to the composition of specific SCFAs in mature HM and newborn feces. Additionally, the percentage of SCFAs gradually decreased from colostrum to mature HM.

Human milk whey proteins: Constituents, influencing factors, detection methods, and comparative analysis with other sources

Whey proteins, the most abundant proteins in human milk (HM), play a vital role in the growth and development of infants. This review first elaborates on the main components of HM whey proteins, including various proteins with specific functions, and details the functions of these proteins in terms of infant nutrition, immunity, as well as growth and development. Secondly, it analyzes factors that affect HM whey proteins, such as maternal differences, dietary habits, and geographical differences. Thirdly, it discusses detection methods for HM whey proteins, covering the principles, advantages, and limitations of different technical means. Finally, it compares whey proteins from different milk sources, highlighting their differences in composition, function, and characteristics. This review aims to comprehensively present the current research status of HM whey protein, provide a scientific basis for maternal and infant health, and contribute to optimizing infant feeding strategies and the research and development of related products.

Maternal probiotic mixture supplementation optimizes the gut microbiota structure of offspring piglets through the gut-breast axis

Delivery and weaning are major stressful events in sows and piglets, adversely affecting production and growth performance and causing economic losses to swine farms. Probiotics as safe antibiotic alternatives have great potential for use across all stages of livestock farming. Here, 18 pregnant sows from clinical farms randomly were divided into two groups: one fed a basal diet (CON group) and the other fed a basal diet plus a probiotic mixture CBB-mix (containing 1×1012 CFU/g of Lactobacillus johnsonii [CJ21], 1×109 CFU/g of Bacillus subtilis [BS15], and 1×109 CFU/g of Bacillus licheniformis [BL21]), for 20 days before delivery. The effects of maternal CBB-mix supplementation on sow colostrum metabolome and offspring piglets' clinical performance, immune status, and gut microbiota were investigated. Additionally, 177 piglets were randomly divided into 4 groups, including CC group (piglets and sows fed a basal diet, n = 40 from 5 litters), CP group (piglets fed the basal diet plus CBB-mix and sows fed the basal diet, n = 38 from 4 litters), PC group (piglets fed the basal diet and sows fed the basal diet plus CBB-mix, n = 50 from 4 litters), and PP group (both piglets and sows fed the basal diet plus CBB-mix, n = 49 from 5 litters). Among that, CP and PP groups were added CBB-mix in the creep feed from 11 days of age for 18 days to study the direct effects of CBB-mix on the growth performance of piglets. Maternal CBB-mix supplementation improved sow production performance, including litter size at birth and litter weight at birth (P < 0.05). Piglets born from CBB-mix-fed sows exhibited increased litter size at weaning and reduced diarrhea incidence from 1 to 10 days of age (P < 0.05). Additionally, systemic immune status and antioxidant capabilities were improved in both sows and piglets. Maternal CBB-mix supplementation reconstituted the gut microbiota structure and increased the Sobs index and Shannon index of fecal microbiota in both sows and piglets (P < 0.05). The relative abundance of Firmicutes and Clostridium_sensu_stricro_1 in sow feces was decreased after feeding CBB-mix (P < 0.05). In piglets, 10-day-old feces had relatively more Lactobacillus but less Escherichia-Shigella than 1-day-old feces (P < 0.05), indicating that maternal feeding CBB-mix alone affects the gut microbiota community of offspring piglets via the gut-breast axis. Piglets born from CBB-mix-fed sows had continuously decreased the relative abundance of fecal Escherichia-Shigella at 28 days of age (P < 0.05). Consistently, the metabolite profile in sow milk was also changed by CBB-mix. Colostrum metabolome showed that CBB-mix significantly regulated tryptophan metabolism and primary bile acid biosynthesis. Our data demonstrated that maternal CBB-mix supplementation effectively improved the production performance of sows and their offsprings' growth performance. Through the gut-breast axis (interaction between gut microbiota and mammary glands), feeding CBB-mix to sows impacted the gut microbiota of their offspring. This study provides strategy and evidence for maternal probiotic supplementation to improve immune status and gut microbiota homeostasis in response to delivery and weaning.

Role of Hindmilk in Weight Gain of Preterm Low-Birth-Weight Neonates: A Prospective Comparative Study

Background The significance of low birth weight cannot be overstated when considering the mortality rates during the perinatal and neonatal stages. Babies who were born premature, especially those with extremely low birth weights, have significant health challenges and require adequate feeding to grow and develop well. Specifically, hindmilk is rich in essential nutrients for neonate growth and development. This study aims to evaluate how hindmilk impacts the weight gain and anthropometry (specifically occipitofrontal circumference and length) of preterm low-birth-weight neonates. Methods A prospective comparative study was conducted on 148 preterm low-birth-weight neonates admitted to the neonatal intensive care unit of a tertiary care hospital in Vijayapura, part of Northern Karnataka. Informed consent was taken and scrutinized by the Institutional Review Board of BLDE University (approval number: BLDE(DU)/IEC/653/2022-23). The neonates were categorized as Group 1, which received hindmilk, or Group 2, which received composite milk based on the computer-generated block randomization list by the investigator. Weight gain and anthropometry were measured and analyzed using SPSS Statistics version 20 (IBM Corp., Released 2011; IBM SPSS Statistics for Windows, Version 20.0; Armonk, NY: IBM Corp.) at the end of the study. Results Group 1 neonates exhibited significantly higher mean values for weight at discharge (1664.22 ± 328.9 grams vs. 1542.33 ± 369.24 grams, p = 0.03), head circumference (31.72 ± 2.52 centimeters (cm) vs. 30.76 ± 4.01 cm, p = 0.04), and length (44.10 ± 2.84 cm vs. 42.23 ± 3.76 cm, p = 0.00) compared to Group 2. Conclusion To enhance the growth outcomes of low-birth-weight preterm neonates, selective hindmilk feeding is highly recommended. Hence, it should be adopted in neonatal care to optimize growth and development.

Maternal Overweight and Obesity and Their Effect on the Growth of the Newborn During the First Six Months of Life

INTRODUCTION

 Maternal overweight and obesity during pregnancy have been shown to have multiple negative effects on the mother's health, which can even affect the infant's growth by increasing weight gain and altering various indicators, such as weight for age, length for age and weight for length. While breast milk on the other hand reduces these risks, and it's the best and most complete food for the newborn. It's a dynamic fluid capable of being modified to meet the needs of each stage of the newborn, but despite this capacity and the fact that maternal body mass index can have an impact on its components, through complex biological mechanisms, it manages to reduce the negative effects accumulated during pregnancy and even promotes a healthy state in the baby. In a country like Mexico, where overweight and obesity affect a large part of the population, it is important to study their causes and which could be the effect of this increased maternal overweight during pregnancy and lactation on newborns.

OBJECTIVE

Identify the alterations associated with increased maternal body mass index during pregnancy and breastfeeding on mothers' health and their possible effect on the growth of the newborn during the first six months of life.

MATERIAL AND METHODS

This was a prospective cohort study. Forty-two healthy binomials (mother and child), without problems during delivery and without serious illnesses during the breastfeeding period, were included. Maternal body mass index at the beginning of pregnancy allowed us to create two comparison groups between mothers: one with adequate weight, another with overweight or obesity. Follow-up was carried out once a month during the first six months of life, evaluating the somatometric development of mothers and children. All mothers completed the six-month period of exclusive breastfeeding.

RESULTS

 There were differences between both groups of women. The one that included overweight and obese women compared to the group of women with adequate weight had a higher number of pregnancies, abortions, plasma glucose levels in the third trimester of pregnancy, and a lower number of prenatal control visits and plasma platelet levels (all with p<0.05). Regarding the baby's growth, there was a difference between the weight for length classification at 60-, 120-, 150- and 180-day follow-ups. The group to which the mother was assigned with respect to her body mass index at the beginning of pregnancy (adequate weight group and overweight/obese group) was the only factor associated with the risk of the baby being overweight according to weight for length indicator at the 180-day follow-up, with an OR = 5.2 (95%CI 1.02-26.59).

CONCLUSIONS

Maternal overweight and obesity during pregnancy have a negative effect on the mother's health and baby's weight gain in its weight-for-length classification during the first six months of life. Although breastfeeding has been shown to have a positive effect on the growth of the baby, exposure to a higher maternal body mass index during pregnancy triggers important metabolic alterations that promote the development of diseases. It is important to establish weight control guidelines in women who wish to become pregnant to reduce the negative effects on the mother and offspring.

Composition of breast milk from mothers of premature and full-term infants and its influence in Z-Scores for infant physical growth

BACKGROUND

Breast milk contains various crucial nutrients and biologically active substances and is ideal for newborns. This study aimed to analyze the composition of breast milk from mothers of premature and full-term infants and its influences on the growth of infants.

METHODS

Infant-mother dyads examined at our Hospital (March 2016 to May 2017) were included. Milk was collected at 0-1 month, 2-3 months, and 5-6 months and analyzed using a MIRIS human milk analyzer. Z-scores of weight-for-length (WLZ), weight-for-age (WAZ), and length-for-age (LAZ) were calculated.

RESULTS

This study included full-term (> 37 weeks of gestation, n = 177) and premature (< 37 weeks, n = 94) infant-mother dyads. The premature infants showed higher ΔWAZ, ΔLAZ, and ΔWLZ from infancy to toddlerhood for the physical growth speed, compared with term infants (P < 0.001). All proteins and true protein components of breast milk decreased with infants' age (P < 0.001). For premature and full-term infants, differences in ΔWAZ and ΔLAZ from birth to infancy and the difference in ΔLAZ, WAZ, and LAZ in toddlerhood were positively associated with non-protein nitrogen (NPN) (all P < 0.05), while the Z-score differences in ΔWLZ from birth to infancy were negatively associated with NPN (all P < 0.05). For premature babies, from birth to infancy stage, ΔWAZ was positively correlated with NPN and carbohydrates while negatively correlated with dry matter (all P < 0.05), and ΔLAZ correlated with NPN (β = 0.428, P = 0.005).

CONCLUSION

Breastfeeding helped premature infants compensatory growth when compared to term infants. Whileduring early infancy stage ΔWLZ gain was negatively associated with increased amounts of NPN in breast milk. This might mean although NPN increase the Z-scores of weight-for-age and length-for-age, with no rise in adipose tissue mass.

Human Milk Macronutrients and Child Growth and Body Composition in the First Two Years: A Systematic Review

Among exclusively breastfed infants, human milk (HM) provides complete nutrition in the first mo of life and remains an important energy source as long as breastfeeding continues. Consisting of digestible carbohydrates, proteins, and amino acids, as well as fats and fatty acids, macronutrients in human milk have been well studied; however, many aspects related to their relationship to growth in early life are still not well understood. We systematically searched Medline, EMBASE, the Cochrane Library, Scopus, and Web of Science to synthesize evidence published between 1980 and 2022 on HM components and anthropometry through 2 y of age among term-born healthy infants. From 9992 abstracts screened, 57 articles reporting observations from 5979 dyads were included and categorized based on their reporting of HM macronutrients and infant growth. There was substantial heterogeneity in anthropometric outcome measurement, milk collection timelines, and HM sampling strategies; thus, meta-analysis was not possible. In general, digestible carbohydrates were positively associated with infant weight outcomes. Protein was positively associated with infant length, but no associations were reported for infant weight. Finally, HM fat was not consistently associated with any infant growth metrics, though various associations were reported in single studies. Fatty acid intakes were generally positively associated with head circumference, except for docosahexaenoic acid. Our synthesis of the literature was limited by differences in milk collection strategies, heterogeneity in anthropometric outcomes and analytical methodologies, and by insufficient reporting of results. Moving forward, HM researchers should accurately record and account for breastfeeding exclusivity, use consistent sampling protocols that account for the temporal variation in HM macronutrients, and use reliable, sensitive, and accurate techniques for HM macronutrient analysis.

Human milk polyunsaturated fatty acids are related to neurodevelopmental, anthropometric, and allergic outcomes in early life: a systematic review

Polyunsaturated fatty acids are critically important for newborn nutrition and in the trajectory of growth and developmental processes throughout early life. This systematic review (PROSPERO ID: CRD42023400059) critically analyzes literature pertaining to how omega-3 and omega-6 fatty acids in human milk are related to health outcomes in early life. Literature selected for the review were published between 2005 and 2020 and included assessments in healthy term children between 0 and 5 years of age. The studies reported the relation between human milk fatty acids docosahexaenoic acid (C22:6n-3, DHA), eicosapentaenoic acid (C20:5n-3, EPA), alpha-linolenic acid (C18:3n-3, ALA), arachidonic acid (C20:4n-6, AA), and linoleic acid (C18:2n-6, LA) with three domains of health outcomes: neurodevelopment, body composition, and allergy, skin & eczema. Results from the 21 studies consistently suggested better health outcomes across the three domains for infants consuming milk with higher concentrations of total n-3, DHA, EPA, and ALA. Negative health outcomes across the three domains were associated with higher levels of total n-6, AA, and LA in milk. N-3 and n-6 content of milk were related to neurodevelopmental, body composition, and allergy, skin & eczema outcomes with moderate certainty. Maternal diet impacting milk fatty acid content and fatty acid desaturase genotype modifying physiologic responses to fatty acid intake were prominent gaps identified in the review using the NIH Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies and GRADE approach. This research study can inform baby nutrition product development, and fatty acid intake recommendations or dietary interventions for mothers and children.

Causes of possible excessive weight gain in exclusively breastfed infants in the first six months of life

BACKGROUND

The aim of this study was to describe factors related to the infant, mother, and breastmilk composition that may be associated with excessive weight gain in a cohort of exclusively breastfed infants younger than 6 months of life with excessive weight gain, and to compare these findings with data from a group of normal-weight exclusively breastfed infants.

METHODS

Thirty-six exclusively breastfed infants younger than 6 months of life seen at two health-care centers between July 2016 and 2017 were enrolled in the study. The clinical features of the infants, their mothers, and the macronutrient composition of the breast milk were evaluated. We classified infants according to weight gain velocity between birth and 6 months of life into an excessive weight gain (EWG) and an adequate weight gain (AWG) group.

RESULTS

Mean age at protocol entry was 3.8 months. Thirteen patients were classified as EWG and 23 patients as AWG. Co-sleeping was more often observed in EWG than in AWG infants. Mothers in the EWG group were younger and more often had gained more than 18 kg during pregnancy than those in the AWG group. No significant differences were found in the macronutrient content of the breast milk between both groups.

CONCLUSIONS

Greater weight gain in infants under 6 months of age may be related to greater weight gain of the mother during pregnancy, younger age of the mother, and co-sleeping of the mother and child.

Specific Milk Composition of miR-30b Transgenic Mice Associated with Early Duodenum Maturation in Offspring with Lasting Consequences for Growth

BACKGROUND

Milk composition is complex and includes numerous components essential for offspring growth and development. In addition to the high abundance of miR-30b microRNA, milk produced by the transgenic mouse model of miR-30b-mammary deregulation displays a significantly altered fatty acid profile. Moreover, wild-type adopted pups fed miR-30b milk present an early growth defect.

OBJECTIVE

This study aimed to investigate the consequences of miR-30b milk feeding on the duodenal development of wild-type neonates, a prime target of suckled milk, along with comprehensive milk phenotyping.

METHODS

The duodenums of wild-type pups fed miR-30b milk were extensively characterized at postnatal day (PND)-5, PND-6, and PND-15 using histological, transcriptomic, proteomic, and duodenal permeability analyses and compared with those of pups fed wild-type milk. Milk of miR-30b foster dams collected at mid-lactation was extensively analyzed using proteomic, metabolomic, and lipidomic approaches and hormonal immunoassays.

RESULTS

At PND-5, wild-type pups fed miR-30b milk showed maturation of their duodenum with 1.5-fold (P < 0.05) and 1.3-fold (P < 0.10) increased expression of Claudin-3 and Claudin-4, respectively, and changes in 8 duodenal proteins (P < 0.10), with an earlier reduction in paracellular and transcellular permeability (183 ng/mL fluorescein sulfonic acid [FSA] and 12 ng/mL horseradish peroxidase [HRP], respectively, compared with 5700 ng/mL FSA and 90 ng/mL HRP in wild-type; P < 0.001). Compared with wild-type milk, miR-30b milk displayed an increase in total lipid (219 g/L compared with 151 g/L; P < 0.05), ceramide (17.6 μM compared with 6.9 μM; P < 0.05), and sphingomyelin concentrations (163.7 μM compared with 76.3 μM; P < 0.05); overexpression of 9 proteins involved in the gut barrier (P < 0.1); and higher insulin and leptin concentrations (1.88 ng/mL and 2.04 ng/mL, respectively, compared with 0.79 ng/mL and 1.06 ng/mL; P < 0.01).

CONCLUSIONS

miR-30b milk displays significant changes in bioactive components associated with neonatal duodenal integrity and maturation, which could be involved in the earlier intestinal closure phenotype of the wild-type pups associated with a lower growth rate.

Does human milk composition predict later risk of obesity? A systematic review

BACKGROUND

Possible mechanisms behind the association of breastfeeding with a lower risk of later obesity are unknown but one possibility is the unique composition of human milk. Here, we systematically reviewed the evidence linking breast-milk macronutrient and hormonal composition with later obesity.

METHODS

We searched 7 databases for studies that included infants predominantly breast-fed for the first 3 months and which analysed associations between a measure of breast-milk composition and later (> 6 months) measures of obesity or body composition.

RESULTS

47 publications were identified for full-text screening, of which 10 were eligible and only 3 found significant associations. Higher leptin concentration in breast milk at age 1 month was associated with lower infant BMI at 12, 18 and 24 months of age (1 study). Higher breast-milk adiponectin concentration at 6 weeks and 4 months were associated with adiposity at age 12 and 24 months (1 study). In 1 study, breast-milk carbohydrate content was positively associated, and fat content negatively associated, with adiposity at age 12 months. No significant associations were found between other hormones or macronutrients in human milk and later risk of obesity or body composition.

CONCLUSIONS

The evidence linking breast-milk composition with later obesity was inconsistent and confined to single, individual studies. Our review highlights the methodological limitations of previous studies and the need for further research in this area.

Associations between breast milk intake volume, macronutrient intake and infant growth in a longitudinal birth cohort: the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF)

Growth patterns of breastfed infants show substantial inter-individual differences, partly influenced by breast milk (BM) nutritional composition. However, BM nutritional composition does not accurately indicate BM nutrient intakes. This study aimed to examine the associations between both BM intake volumes and macronutrient intakes with infant growth. Mother-infant dyads (n 94) were recruited into the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF) from a single maternity hospital at birth; all infants received exclusive breast-feeding (EBF) for at least 6 weeks. Infant weight, length and skinfolds thicknesses (adiposity) were repeatedly measured from birth to 12 months. Post-feed BM samples were collected at 6 weeks to measure TAG (fat), lactose (carbohydrate) (both by 1H-NMR) and protein concentrations (Dumas method). BM intake volume was estimated from seventy infants between 4 and 6 weeks using dose-to-the-mother deuterium oxide (2H2O) turnover. In the full cohort and among sixty infants who received EBF for 3+ months, higher BM intake at 6 weeks was associated with initial faster growth between 0 and 6 weeks (β + se 3·58 + 0·47 for weight and 4·53 + 0·6 for adiposity gains, both P < 0·0001) but subsequent slower growth between 3 and 12 months (β + se - 2·27 + 0·7 for weight and -2·65 + 0·69 for adiposity gains, both P < 0·005). BM carbohydrate and protein intakes at 4-6 weeks were positively associated with early (0-6 weeks) but tended to be negatively related with later (3-12 months) adiposity gains, while BM fat intake showed no association, suggesting that carbohydrate and protein intakes may have more functional relevance to later infant growth and adiposity.

Obesity in Early Life: Its Causes, Prevention and Risks in Later Life

Being overweight or obese at the end of the first year of life is associated with an increased risk of obesity in later life and an increased risk of developing other diseases, like type 1 diabetes mellitus, cardiovascular disorders and psycho-social problems [...].

Butyrate in Human Milk: Associations with Milk Microbiota, Milk Intake Volume, and Infant Growth

Butyrate in human milk (HM) has been suggested to reduce excessive weight and adipo-sity gains during infancy. However, HM butyrate's origins, determinants, and its influencing mechanism on weight gain are not completely understood. These were studied in the prospective longitudinal Cambridge Baby Growth and Breastfeeding Study (CBGS-BF), in which infants (n = 59) were exclusively breastfed for at least 6 weeks. Infant growth (birth, 2 weeks, 6 weeks, 3 months, 6 months, and 12 months) and HM butyrate concentrations (2 weeks, 6 weeks, 3 months, and 6 months) were measured. At age 6 weeks, HM intake volume was measured by deuterium-labelled water technique and HM microbiota by 16S sequencing. Cross-sectionally at 6 weeks, HM butyrate was associated with HM microbiota composition (p = 0.036) although no association with the abundance of typical butyrate producers was detected. In longitudinal analyses across all time points, HM butyrate concentrations were overall negatively associated with infant weight and adiposity, and associations were stronger at younger infant ages. HM butyrate concentration was also inversely correlated with HM intake volume, supporting a possible mechanism whereby butyrate might reduce infant growth via appetite regulation and modulation of HM intake.

Interaction between maternal dietary fat intake, breast milk omega-3 fatty acids and infant growth during the first year of life

BACKGROUND

Long chain fatty acids (LCFA) of human milk (HM) might be associated with different patterns of weight gain in infancy. This study aims to examine the interaction between maternal dietary fat intake, breast milk content of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) with infant growth during the first year of life.

METHODS

This longitudinal study was conducted among 215 Iranian mother-infant pairs. The infants were followed up from birth to 12 months of age. Trained healthcare providers measured infant anthropometrics including weight, length and head circumference at birth, 2, 4, 6 and 12 months of age. Breast hind milk samples were collected in the morning through hand expression between 6 and 12 weeks postpartum. Maternal dietary intake was assessed using a 3-day dietary record. Linear mixed effects models were performed to determine the interaction between maternal dietary fat intake, the breast milk content of EPA and DHA with infant growth. Further adjustments were applied for potential confounders.

RESULTS

Mean and standard deviation (SD) of maternal age and body mass index were 29.70 (5.24) years and 24.47 (4.42) kg/m² , respectively. Mean (SD) of infant birth weight was 3177.50 (413.20) g, and 50% were boys. An inverse interaction existed between maternal dietary fat intake and breast milk EPA with infant 4-month weight (β: -366.2, P-value: 0.01). We found a significant association of maternal dietary fat intake and infant 6-month weight (β: 22.5, P-value: 0.04). An inverse interaction was documented between maternal dietary fat intake and breast milk DHA with infant weight at 12-month of age (β: -95.3, P-value: 0.02). We found a significant association between maternal dietary fat intake and infant length at 12-month (β: 0.06, P-value: 0.02).

CONCLUSION

We found an inverse interaction between maternal dietary fat intake and breast milk omega-3 fatty acids with infant weight at 4 and 12 months of age. Although longer follow-up of growth indices is recommended, these findings suggest functional relevance of HM composition to infant growth.

Gestational Diabetes Mellitus, Human Milk Composition, and Infant Growth

Background: Gestational diabetes mellitus (GDM) is known to affect human milk composition. Aims of this study were to compare macronutrient and energy content of human milk of women with (GDM⁺) and without GDM (GDM^-), to assess the association between maternal health and human milk macronutrient and energy content and association between human milk macronutrient and energy content and infant growth. Study Design and Methods: Two months after delivery, hindmilk samples were collected. Triglyceride (TG), lactose, and protein content of human milk were measured. An oral glucose tolerance test was performed. Infant weight and length at birth and 2 months were collected. Weight-for-age (WAZ) and weight-for-length z-scores were calculated. Results: Twenty-four GDM⁺ and 29 GDM^- women were included. Protein, lactose, and energy content of human milk were similar between groups. TG concentration was higher in GDM⁺ than in GDM^- women (6.3 ± 2.0 versus 5.3 ± 1.2, p = 0.04). This difference was no longer significant after adjustment for maternal age and infant sex (p = 0.23). Maternal age was associated with TG (r = 0.28, p = 0.04) and lactose (r = -0.30, p = 0.03), while fasting glucose was associated with proteins (r = 0.30, p = 0.03) and tended to be associated with TG (r = 0.27, p = 0.05) and energy (r = 0.24, p = 0.08). TG levels in human milk were associated with weight (β: 0.26, 95% confidence interval [CI]: 0.02 to 0.50) and WAZ (β: 0.40, 95% CI: 0.05 to 0.75) at 2 months among children unexposed (GDM^-) to GDM, but not among children exposed (GDM⁺) Conclusions: In conclusion, GDM status, maternal age, and fasting glucose level were associated with human milk composition. Finally, TG in human milk was associated with infant growth among GDM^- children but not among GDM⁺ children. ClinicalTrials.gov NCT02872402.

Galectins-1, -3 and -9 Are Present in Breast Milk and Have a Role in Early Life Development

Galectins (Gal) are a family of conserved soluble proteins with high affinity for β-galactoside structures. They have been recognized as important proteins for successful pregnancy. However, little is known about their presence in breast milk and their role in early infancy. Gal-1, -3 and -9 concentrations were evaluated by Multiplex immunoassays in mother–infant pairs from the MAMI cohort in maternal plasma (MP) (n = 15) and umbilical cord plasma (UCP) (n = 15) at birth and in breast milk samples (n = 23) at days 7 and 15 postpartum. Data regarding mother and infant characteristics were collected. Gal-9 was present in a lower concentration range than Gal-1 and Gal-3 in plasma, specifically in UCP. A major finding in the current study is that Gal-1, -3 and -9 were detected for the first time in all the transitional breast milk samples and no differences were found when comparing the two breastfeeding time points. Finally, Gal levels were associated with some maternal and infant characteristics, such as gestational age, pregnancy weight gain, maternal diet, the gender, infant growth and infant infections. In conclusion, Gal levels seem to be involved in certain developmental aspects of early life.

Predictors of Human Milk Fatty Acids and Associations with Infant Growth in a Norwegian Birth Cohort

Triglyceride-bound fatty acids constitute the majority of lipids in human milk and may affect infant growth. We describe the composition of fatty acids in human milk, identify predictors, and investigate associations between fatty acids and infant growth using data from the Norwegian Human Milk Study birth cohort. In a subset of participants (n = 789, 30% of cohort), oversampled for overweight and obesity, we analyzed milk concentrations of detectable fatty acids. We modelled percent composition of fatty acids in relation to maternal body mass index, pregnancy weight gain, parity, smoking, delivery mode, gestational age, fish intake, and cod liver oil intake. We assessed the relation between fatty acids and infant growth from 0 to 6 months. Of the factors tested, excess pregnancy weight gain was positively associated with monounsaturated fatty acids and inversely associated with stearic acid. Multiparity was negatively associated with monounsaturated fatty acids and n-3 fatty acids while positively associated with stearic acid. Gestational age was inversely associated with myristic acid. Medium-chain saturated fatty acids were inversely associated with infant growth, and mono-unsaturated fatty acids, particularly oleic acid, were associated with an increased odds of rapid growth. Notably, excessive maternal weight gain was associated with cis-vaccenic acid, which was further associated with a threefold increased risk of rapid infant growth (OR = 2.9, 95% CI 1.2–6.6), suggesting that monounsaturated fatty acids in milk may play a role in the intergenerational transmission of obesity.

Exploring the Potential of Human Milk and Formula Milk on Infants’ Gut and Health

Early-life gut microbiota plays a role in determining the health and risk of developing diseases in later life. Various perinatal factors have been shown to contribute to the development and establishment of infant gut microbiota. One of the important factors influencing the infant gut microbial colonization and composition is the mode of infant feeding. While infant formula milk has been designed to resemble human milk as much as possible, the gut microbiome of infants who receive formula milk differs from that of infants who are fed human milk. A diverse microbial population in human milk and the microbes seed the infant gut microbiome. Human milk contains nutritional components that promote infant growth and bioactive components, such as human milk oligosaccharides, lactoferrin, and immunoglobulins, which contribute to immunological development. In an attempt to encourage the formation of a healthy gut microbiome comparable to that of a breastfed infant, manufacturers often supplement infant formula with prebiotics or probiotics, which are known to have a bifidogenic effect and can modulate the immune system. This review aims to elucidate the roles of human milk and formula milk on infants’ gut and health.

Uncontrolled Thyroid during Pregnancy Alters the Circulative and Exerted Metabolome

Normal levels of thyroid hormones (THs) are essential for a normal pregnancy outcome, fetal growth and the normal function of the central nervous system. Hypothyroidism, a common endocrine disorder during pregnancy, is a significant metabolic factor leading to cognitive impairments. It is essential to investigate whether patients with thyroid dysfunction may present an altered circulative and excreted metabolic profile, even after receiving treatment with thyroxine supplements. NMR metabolomics was employed to analyze 90 serum and corresponding colostrum samples. Parallel analyses of the two biological specimens provided a snapshot of the maternal metabolism through the excretive and circulating characteristics of mothers. The metabolomics data were analyzed by performing multivariate statistical, biomarker and pathway analyses. Our results highlight the impact of hypothyroidism on metabolites’ composition during pregnancy and lactation. Thyroid disorder causing metabolite fluctuations may lead to impaired lipid and glucose metabolic pathways as well as aberrant prenatal neurodevelopment, thus posing a background for the occurrence of metabolic syndrome or neurogenerative diseases later in life. This risk applies to not only untreated but also hypothyroid women under replacement therapy since our findings in both biofluids framed a different metabolic phenotype for the latter group, thus emphasizing the need to monitor women adequately after treatment initiation.

Detailed knowledge of maternal and infant factors and human milk composition could inform recommendations for optimal composition

Breastfeeding is best for infants, but quantitative associations between specific milk components and infant biomarkers remain unclear. Methodological limitations include missing milk volume intake, variable milk composition and that standardised, fasted state blood sampling is impossible in infants. Milk protein and fat content appear marginally related to infant serum amino acid and phospholipid concentrations, with some association between milk fatty acid composition and lipid species levels. CONCLUSION: Detailed simultaneous examinations of maternal factors, milk composition and infant biomarkers or outcomes could identify the mechanistic basis of human milk effects and help develop dietary recommendations for optimal human milk composition.

Non-Cholesterol Sterols in Breast Milk and Risk of Allergic Outcomes in the First Two Years of Life

This study aimed to explore associations between non-cholesterol sterol concentrations in breast milk and allergic outcomes in children aged two. Data from the KOALA Birth Cohort Study, the Netherlands, were used. Non-cholesterol sterols were analyzed by gas–liquid chromatography–mass spectrometry in breast milk sampled one-month postpartum (N = 311). Sterols were selected for each allergic outcome, i.e., eczema, wheeze, and allergic sensitization, prior to analyses. Associations between the selected sterols with allergic outcomes were analyzed using multiple logistic regression to calculate odds ratios (ORs). The odds of eczema in the first two years of life were lower with higher concentrations of cholestanol (OR (95%CI): 0.98 (0.95; 1.00), p = 0.04), lanosterol (0.97 (0.95; 1.00), p = 0.02), lathosterol (0.93 (0.87; 0.99), p = 0.02), and stigmasterol (0.51 (0.29; 0.91), p = 0.02) in breast milk sampled one-month postpartum. None of the sterols were associated with wheeze in the first two years of life. The odds of allergic sensitization at age two were lower with higher concentrations of campesterol in breast milk (OR (95%CI): 0.81 (0.70; 0.95), p = 0.01). In conclusion, our data suggest that exposure to higher non-cholesterol sterol concentrations in breast milk may indeed be associated with the prevention of allergic outcomes in the first two years of life.

Comparative Proteomics Study of Yak Milk from Standard and Naturally Extended Lactation Using iTRAQ Technique

Extended lactation is a common phenomenon in lactating yaks under grazing and natural reproduction conditions. To elucidate differences in milk protein compositions and mammary gland functions between yaks of standard lactation (TL yaks) and prolonged lactation (HL yaks), whole milk samples of TL yaks and HL yaks (n = 15 each) were collected from a yak pasture at the northwest highland of China. The iTRAQ technique was used to compare the skim milk proteins in the two yak groups. A total of 202 differentially expressed proteins (DEPs) were revealed, among which 109 proteins were up-regulated and 93 were down-regulated in the milk of HL yaks compared to TL yaks. Caseins including κ-casein, αs1-casein, αs2-casein, and β-casein were up-regulated in HL yak milk over 1.43-fold. The GO function annotation analysis showed that HL yaks produced milk with characteristics of milk at the degeneration stage, similar to that of dairy cows. KEGG enrichment showed that the metabolic pathways with the most differences are those that involve carbohydrate metabolism and the biosynthesis of amino acids. The present results highlight detailed differences in skim milk proteins produced by HL yaks and TL yaks and suggest that the mammary gland of HL yak is at the degeneration stage.

The effect of postpartum family visits on the promotion of breastfeeding and improvement of maternal and infant health

OBJECTIVE

The study was designed to explore the effect of postpartum family visits on the promotion of breastfeeding and the improvement of maternal and infant health.

METHODS

A total of 200 cases of parturients who gave birth in our hospital from January 2019 to January 2020 were selected as the research participants. According to a randomized, double-blinded and controlled manner, they were divided into a study group (n=100, with postpartum family visits) and a control group (n=100, without postpartum family visits). The amount of lactation, breastfeeding status, knowledge of breastfeeding health, and the incidence of maternal adverse events were compared between the two groups at different follow-up times after intervention. The physical development of infants and the occurrence of adverse events were also compared.

RESULTS

The lactation of the parturients in the study group at 28, 60, and 120 days after delivery was significantly higher than that of the control group, and the proportion of exclusive breastfeeding of the study group was higher than that of the control group (P<0.05). The comparison of 120 days after delivery showed that the knowledge of breastfeeding health and self-confidence in breastfeeding in the study group were better than those in the control group (P<0.05). The 120-day postpartum evaluation showed that there was no significant difference in the height and weight of the infants between the two groups (P>0.05). The incidence of maternal and neonatal adverse events of the study group was lower than that of the control group (P<0.05).

CONCLUSION

Postpartum family visits for parturients can help improve breastfeeding, increase maternal knowledge of breastfeeding health, and also help reduce the incidence of various adverse events of parturients and infants, which is worthy of clinical application.

A one-year study of human milk oligosaccharide profiles in the milk of healthy UK mothers and their relationship to maternal FUT2 genotype

Human milk oligosaccharides (HMOs) are indigestible carbohydrates with prebiotic, pathogen decoy and immunomodulatory activities that are theorized to substantially impact infant health. The objective of this study was to monitor HMO concentrations over 1 year to develop a long-term longitudinal dataset. HMO concentrations in the breast milk of healthy lactating mothers of the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF) were measured at birth, 2 weeks, 6 weeks, 3 months, 6 months and 12 months postpartum. HMO quantification was conducted by high-performance anion-exchange chromatography with pulsed amperometric detection using a newly validated "dilute-and-shoot" method. This technique minimizes sample losses and expedites throughput, making it particularly suitable for the analysis of large sample sets. Varying patterns of individual HMO concentrations were observed with changes in lactation timepoint and maternal secretor status, with the most prominent temporal changes occurring during the first 3 months. These data provide valuable information for the development of human milk banks in view of targeted distribution of donor milk based on infant age. Maternal FUT2 genotype was determined based on identification at single-nucleotide polymorphism rs516246 and compared with the genotype expected based on phenotypic markers in the HMO profile. Surprisingly, two mothers genotyped as secretors produced milk that displayed very low levels of 2'-fucosylated moieties. This unexpected discrepancy between genotype and phenotype suggests that differential enzyme expression may cause substantial variation in HMO profiles between genotypically similar mothers, and current genotypic methods of secretor status determination may require validation with HMO markers from milk analysis.

Protein Quality in Infant Formulas Marketed in Brazil: Assessments on Biodigestibility, Essential Amino Acid Content and Proteins of Biological Importance

Infant formulas, designed to provide similar nutritional composition and performance to human milk, are recommended when breastfeeding is not enough to provide for the nutritional needs of children under 12 months of age. In this context, the present study aimed to assess the protein quality and essential amino acid content of both starting (phase 1) and follow-up (phase 2) formulas from different manufacturers. The chemical amino acid score and protein digestibility corrected by the amino acid score were calculated. The determined protein contents in most formulas were above the maximum limit recommended by FAO and WHO guidelines and at odds with the protein contents declared in the label. All infant formulas contained lactoferrin (0.06 to 0.44 g·100 g⁻¹) and α-lactalbumin (0.02 to 1.34 g·100 g⁻¹) below recommended concentrations, whereas ĸ-casein (8.28 to 12.91 g·100 g⁻¹), α-casein (0.70 to 2.28 g·100 g⁻¹) and β-lactoglobulin (1.32 to 4.19 g·100 g⁻¹) were detected above recommended concentrations. Essential amino acid quantification indicated that threonine, leucine and phenylalanine were the most abundant amino acids found in the investigated infant formulas. In conclusion, infant formulas are still unconforming to nutritional breast milk quality and must be improved in order to follow current global health authority guidelines.

Human Milk Lactose, Insulin, and Glucose Relative to Infant Body Composition during Exclusive Breastfeeding

Human milk (HM) components may influence infant growth and development. This study aimed to investigate relationships between infant body composition (BC) and HM lactose, insulin, and glucose (concentrations and calculated daily intakes (CDI)) as well as 24-h milk intake and maternal BC at 3 months postpartum. HM samples were collected at 2 months postpartum. Infant and maternal BC was assessed with bioimpedance spectroscopy. Statistical analysis used linear regression accounting for infant birth weight. 24-h milk intake and CDI of lactose were positively associated with infant anthropometry, lean body mass and adiposity. Higher maternal BC measures were associated with lower infant anthropometry, z-scores, lean body mass, and adiposity. Maternal characteristics including BC and age were associated with concentrations and CDI of HM components, and 24-h milk intake. In conclusion, 24-h intake of HM and lactose as well as maternal adiposity are related to development of infant BC.

Polychlorinated biphenyls (PCBs) in the colostrum samples from the Yangtze River Region: Exposure profile and risk assessment

Polychlorinated biphenyls (PCBs) may transfer into the neonates through the placental transfer and via breastfeeding after the delivery, thus might be harmful to the infant. Sixty colostrum samples in the Yangtze River Region were collected to investigate the concentration, distribution pattern, and enantiomer characteristic of the PCB exposure. Among all samples, over 90% of pollutants were tetra-to hepta-chlorinated PCBs. The sum concentration of the PCB was 512 (IQR: 322-856) ng g^-1 lipid weight. Enantiomer fraction (EF) of PCB 95 and PCB 149 was found lower than the racemic value, while EFs of PCB 45 and PCB 136 were found higher and near-racemic state, respectively. The concentration pattern and enantiomeric properties of the PCBs indicated that the mothers from Mianyang had a recent exposure to PCBs. Among all samples, similar exposure and metabolic pathways of the PCB congeners were observed. PCB exposure showed no significant correlation with the birth outcome of the infants, but 43.3% of the infants have potential health risks via breastfeeding.

Extensive Study of Breast Milk and Infant Growth: Protocol of the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF)

Growth and nutrition during early life have been strongly linked to future health and metabolic risks. The Cambridge Baby Growth Study (CBGS), a longitudinal birth cohort of 2229 mother-infant pairs, was set up in 2001 to investigate early life determinant factors of infant growth and body composition in the UK setting. To carry out extensive profiling of breastmilk intakes and composition in relation to infancy growth, the Cambridge Baby Growth and Breastfeeding Study (CBGS-BF) was established upon the original CBGS. The strict inclusion criteria were applied, focusing on a normal birth weight vaginally delivered infant cohort born of healthy and non-obese mothers. Crucially, only infants who were exclusively breastfed for the first 6 weeks of life were retained in the analysed study sample. At each visit from birth, 2 weeks, 6 weeks, and then at 3, 6, 12, 24, and 36 months, longitudinal anthropometric measurements and blood spot collections were conducted. Infant body composition was assessed using air displacement plethysmography (ADP) at 6 weeks and 3 months of age. Breast milk was collected for macronutrients and human milk oligosaccharides (HMO) measurements. Breast milk intake volume was also estimated, as well as sterile breastmilk and infant stool collection for microbiome study.

Effect of weaning method on body weight, testicular growth, sexual behavior, age of puberty, and testosterone concentration of Beetal bucks

The current study evaluates the effects of early (8th week) and late (16th week of age) weaning of male goat kids on their body growth, testicular growth, sexual behavior, plasma testosterone concentration, and pubertal age. Early (n = 6) and late (n = 7) weaned Beetal bucks were weekly monitored from 18th to 38th week for their body weight, scrotal circumference, testicular volume, testicular echogenicity (via ultrasonography), sexual activities, and plasma testosterone concentration. In comparison to early-weaned, late-weaned bucks showed a marked increase (p < .05) in body weight (11.4 ± 0.8 vs. 13.7 ± 0.6kg), testicular volume (44.1 ± 7.2 vs. 79.8 ± 18.7cm³ ), scrotal circumference (10.7 ± 0.6 vs. 12.8 ± 0.7cm), and testicular echogenicity (28.3 ± 2.7 vs. 38.3 ± 2.1) from 18th, 28th, 21st, and 24th week onward, respectively. Sexual activities started earlier in late- than early-weaned bucks (22nd vs. 25th week, respectively). Moreover, the sexual behavior index was better (p < .05) after the 34th week in late than early-weaned bucks. The plasma concentration of testosterone (at 39 weeks of age) was relatively more and the onset of puberty was 2-3 weeks earlier (p < .05) in late than early-weaned bucks. In conclusion, age-based early weaning of male kids impairs their testicular growth, sexual behavior, and age at puberty compared to conventional weaning.

Free and Total Amino Acids in Human Milk in Relation to Maternal and Infant Characteristics and Infant Health Outcomes: The Ulm SPATZ Health Study

Free amino acids (FAAs) are important regulators of key pathways necessary for growth, development, and immunity. Data on FAAs in human milk (HM) and their roles in infant development are limited. We investigated the levels of FAAs and total amino acids (TAA, i.e., the sum of conjugated amino acids and FAAs) in HM in relation to infant and maternal characteristics and immunological conditions. FAA and TAA levels in HM sampled at 6 weeks (n = 671) and 6 months (n = 441) of lactation were determined using high-performance liquid chromatography. Child growth was ascertained at 4–5 weeks and at 6–7 months of age. Child allergy and lower respiratory tract infections were assessed in the first years of life. Associations of amino acid (AA) levels in HM with child growth and health outcomes were determined by Spearman correlation and modified Poisson regression, respectively. Free glutamine, glutamate, and serine in 6-week HM positively correlated with infant weight gain in the first 4–5 weeks of age. Maternal pre-pregnancy weight and body mass index (BMI) were negatively correlated with free glutamine and asparagine in 6-week and 6-month HM and positively correlated with the sum of TAAs in 6-month HM, but significance was lost following confounder adjustment. Free glutamine was lower in 6-month HM of mothers with an allergy (either active or non-active). No consistent associations were found between FAAs in HM and child health outcomes. However, potential negative associations were observed between specific FAAs and the risk of food allergy. These results suggest that specific FAAs play a role in infant growth. Moreover, these findings warrant further investigations into the relation of FAAs in HM with infant health outcomes and maternal allergy.

Reduction in Maternal Energy Intake during Lactation Decreased Maternal Body Weight and Concentrations of Leptin, Insulin and Adiponectin in Human Milk without Affecting Milk Production, Milk Macronutrient Composition or Infant Growth

Maternal diet has the potential to affect human milk (HM) composition, but very few studies have directly assessed the effect of maternal diets on HM composition. The primary aim of this study was to assess the effect of improving dietary quality in lactating women over 2 weeks on the concentrations of macronutrients and metabolic hormones in HM. The secondary aims were to assess the impact of the dietary intervention on 24 h milk production, maternal body composition and infant growth. Fifteen women completed a 1-week baseline period followed by a 2-week dietary intervention phase targeted towards reducing fat and sugar intake. Maternal anthropometric and body composition and infant growth measurements were performed weekly. Total 24 h milk production was measured before and after the dietary intervention, and HM samples were collected daily. Maternal intakes of energy (−33%), carbohydrate (−22%), sugar (−29%), fat (−54%) and saturated fat (−63%) were significantly reduced during the dietary intervention. HM insulin, leptin and adiponectin concentrations were 10–25% lower at the end of the dietary intervention, but HM concentrations of macronutrients were unaffected. Maternal body weight (−1.8%) and fat mass (−6.3%) were significantly reduced at the end of the dietary intervention, but there were no effects on 24 h milk production or infant growth. These results suggest that reducing maternal energy, carbohydrate, fat and sugar intake over a 2-week period is associated with significant reductions in HM insulin, leptin and adiponectin concentrations. These changes may be secondary to decreases in maternal weight and fat mass. The limited studies to date that have investigated the association between metabolic hormone concentrations in HM and infant growth raise the possibility that the changes in HM composition observed in the current study could impact infant growth and adiposity, but further studies are required to confirm this hypothesis.

Daily variation of macronutrient concentrations in mature human milk over 3 weeks

Human milk (HM) composition is known to be highly variable, both between individuals and across the duration of lactation. It is less clear, however, to what extent fat, lactose and protein concentrations in HM change daily over shorter time periods in mature HM, and no studies have evaluated this to date. The aim of this study was to systematically assess and compare HM macronutrient concentrations in samples collected at different times of day, from left and right breasts and daily across a 3-week period in the same woman. Fifteen lactating women (1.6–4.9 months postpartum) collected daily pre-feed HM samples from both breasts each morning for 21 consecutive days and completed intensive sampling once a week (morning, afternoon and evening samples) during this period. Concentrations of fat, protein and lactose in HM did not differ according to time of day, day of week or breast used for collection. The results of this study suggest that pre-feed samples collected at any point across a 3-week period and from either the left or right breast provide comparable measures of fat, protein and lactose concentrations in mature HM, in pragmatic studies where women are collecting their own HM samples.

Clinical trial registration: Australian New Zealand Clinical Trials Registry (ACTRN12619000606189).

Neurodevelopmental toxicity assessment of flame retardants using a human DNT in vitro testing battery

Due to their neurodevelopmental toxicity, flame retardants (FRs) like polybrominated diphenyl ethers are banned from the market and replaced by alternative FRs, like organophosphorus FRs, that have mostly unknown toxicological profiles. To study their neurodevelopmental toxicity, we evaluated the hazard of several FRs including phased-out polybrominated FRs and organophosphorus FRs: 2,2′,4,4′-tetrabromodiphenylether (BDE-47), 2,2′,4,4′,5-pentabromodiphenylether (BDE-99), tetrabromobisphenol A, triphenyl phosphate, tris(2-butoxyethyl) phosphate and its metabolite bis-(2-butoxyethyl) phosphate, isodecyl diphenyl phosphate, triphenyl isopropylated phosphate, tricresyl phosphate, tris(1,3-dichloro-2-propyl) phosphate, tert-butylphenyl diphenyl phosphate, 2-ethylhexyl diphenyl phosphate, tris(1-chloroisopropyl) phosphate, and tris(2-chloroethyl) phosphate. Therefore, we used a human cell–based developmental neurotoxicity (DNT) in vitro battery covering a large variety of neurodevelopmental endpoints. Potency according to the respective most sensitive benchmark concentration (BMC) across the battery ranked from <1 μM (5 FRs), 1<10 μM (7 FRs) to the >10 μM range (3 FRs). Evaluation of the data with the ToxPi tool revealed a distinct ranking (a) than with the BMC and (b) compared to the ToxCast data, suggesting that DNT hazard of these FRs is not well predicted by ToxCast assays. Extrapolating the DNT in vitro battery BMCs to human FR exposure via breast milk suggests low risk for individual compounds. However, it raises a potential concern for real-life mixture exposure, especially when different compounds converge through diverse modes-of-action on common endpoints, like oligodendrocyte differentiation in this study. This case study using FRs suggests that human cell–based DNT in vitro battery is a promising approach for neurodevelopmental hazard assessment and compound prioritization in risk assessment.

Longitudinal Changes in the Concentration of Major Human Milk Proteins in the First Six Months of Lactation and Their Effects on Infant Growth

Our knowledge related to human milk proteins is still limited. The present study determined the changes in multiple human milk proteins during the first six months of lactation, investigated the influencing factors of milk proteins, and explored the impact of milk proteins on infant growth. A total of 105 lactating women and their full-term infants from China were prospectively surveyed in this research. Milk samples were collected at 1–5 days, 8–14 days, 1 month, and 6 months postpartum. Concentrations of total protein and α-lactalbumin were measured in all milk samples, and concentrations of lactoferrin, osteopontin, total casein, β-casein, α_s−1 casein, and κ-casein were measured in milk from 51 individuals using ultra performance liquid chromatography coupled with mass spectrometry. The concentration of measured proteins in the milk decreased during the first six months of postpartum (p-trend < 0.001). Maternal age, mode of delivery, maternal education, and income impacted the longitudinal changes in milk proteins (p-interaction < 0.05). Concentrations of α_s−1 casein in milk were inversely associated with the weight-for-age Z-scores of the infants (1 m: r −0.29, p 0.038; 6 m: r −0.33, p 0.020). In conclusion, the concentration of proteins in milk decreased over the first six months postpartum, potentially influenced by maternal demographic and delivery factors. Milk protein composition may influence infant weights.

Ascending Growth is Associated with Offspring Adiposity in Pregnancies Complicated with Obesity or Gestational Diabetes

CONTEXT

Early growth is associated with childhood adiposity, but the influence of lifestyle remains unknown.

OBJECTIVE

This work aimed to investigate the association of growth profiles from high-risk pregnancies with adiposity at age 5 years, taking into account lifestyle and several antenatal/postnatal exposures.

METHODS

This prospective cohort study.

INCLUDED

609 children born during the Finnish Gestational Diabetes Prevention Study (RADIEL), recruiting women with body mass index (BMI) greater than or equal to 30 and/or prior gestational diabetes mellitus (GDM) (2008-2013). Altogether 332 children attended the 5-year follow-up (2014-2017). Main outcome measures included growth profiles based on ponderal index (PI = weight/height3), investigated using latent class mixed models. Adiposity was assessed with anthropometrics and body composition (InBody720).

RESULTS

We identified 3 growth profiles: ascending (n = 82), intermediate (n = 351), and descending (n = 149). Children with ascending growth had a higher body fat percentage, ISO-BMI, and waist circumference (P < .05) at age 5 years. Ascending (β 4.09; CI, 1.60-6.58) and intermediate (β 2.27; CI, 0.50-4.03) profiles were associated with higher fat percentage, even after adjustment for age, sex, gestational age, diet, physical activity, education, and prepregnancy BMI. Similar associations existed with ISO-BMI. After adjusting for age and education, ascending growth was associated with prepregnancy BMI (odds ratio [OR] 1.06; CI, 1.01-1.12), primiparity (OR 3.07; CI, 1.68-5.62), cesarean delivery (OR 2.23; CI, 1.18-4.21), and lifestyle intervention (OR 2.56; CI, 1.44-4.57). However, meeting the intervention goals and exclusive breastfeeding for 3 months or more were associated with lower odds of ascending growth.

CONCLUSION

Accelerated early growth was associated with higher adiposity in 5-year-old children from high-risk pregnancies, even when adjusted for lifestyle. Reducing cesarean deliveries and promoting breastfeeding may be beneficial for postnatal growth.

Maternal BMI is positively associated with human milk fat: a systematic review and meta-regression analysis

BACKGROUND

Lack of robust estimates of human-milk nutrient composition and influential maternal factors, such as body composition, are barriers to informing nutrition policies and programs.

OBJECTIVE

The objective was to understand the relation between maternal BMI and human-milk energy, fat, and/or total protein.

METHODS

Four electronic databases (MEDLINE, Embase, CINAHL, and Web of Science) were searched. Outcomes assessed were human-milk energy (kcal/L), fat (g/L), and total protein (g/L) from mothers 1 to 6 mo postpartum. Studies with data on maternal BMI or weight and height that quantified human-milk energy, fat, or protein between 1 and 6 mo postpartum were eligible. Random-effects meta-regression weighted by the inverse of the study-level SE was completed for each of the 3 outcomes. The certainty of evidence for each outcome was assessed using the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) approach.

RESULTS

A total of 11,373 titles and abstracts were identified, and after full-text screening, 69 articles of 66 studies were included. Meta-regression results showed a positive association between maternal BMI and human-milk fat (β: 0.56 g/L; 95% CI: 0.034, 1.1; P = 0.04; I2 = 93.7%, n = 63 datapoints). There was no significant association between maternal BMI and human-milk energy (β: 3.9 kcal/L; 95% CI: -1.6, 9.5; P = 0.16, I2 = 93.3%, n = 40 datapoints) or total protein (β: 0.13 g/L; 95% CI: -0.16, 0.41; P = 0.37, I2 = 99.1%, n = 40 datapoints). The certainty of evidence for human-milk energy was low and the certainty of evidence for fat and total protein was very low.

CONCLUSIONS

Meta-regression analysis of available literature suggested an association between maternal BMI and human-milk fat between 1 and 6 mo postpartum. Future studies are needed to confirm the relation between maternal BMI; variation in human-milk energy, fat, and protein content; and the implications for child growth and development. This review is registered with International Prospective Register of Systematic Reviews (PROSPERO 2018 CRD42018098808) at https://www.crd.york.ac.uk/prospero/.

The Gut‒Breast Axis: Programming Health for Life

The gut is a pivotal organ in health and disease. The events that take place in the gut during early life contribute to the programming, shaping and tuning of distant organs, having lifelong consequences. In this context, the maternal gut plays a quintessence in programming the mammary gland to face the nutritional, microbiological, immunological, and neuroendocrine requirements of the growing infant. Subsequently, human colostrum and milk provides the infant with an impressive array of nutrients and bioactive components, including microbes, immune cells, and stem cells. Therefore, the axis linking the maternal gut, the breast, and the infant gut seems crucial for a correct infant growth and development. The aim of this article is not to perform a systematic review of the human milk components but to provide an insight of their extremely complex interactions, which render human milk a unique functional food and explain why this biological fluid still truly remains as a scientific enigma.

The importance of infants' lipid intake in human milk research

Human milk lipids are among the many nutrients delivered to the infant, providing >50% of the infant's calorie intake. These lipids are highly complex and variable, and bioactive, contributing to infant growth, development, and health. The lipid concentration of milk samples is often measured in human cohorts; however, few studies measure infant intake of milk. Intake is important because it considers the variability of both lipid concentration and infants' consumed volume of milk. Measurement of infants' lipid intake in exclusively breastfeeding infants requires 3 main considerations: human milk sampling protocol (ie, the collection of representative samples); measurement of the infant milk intake, because volume varies widely between infants; and appropriate analytical laboratory methods. The purpose of this review was to provide an overview of existing methodology and demonstrate the importance of measuring infants' lipid intake to understand the impact that human milk lipids have on infant outcomes.

Overweight in childhood of exclusively breastfed infants with a high weight at 5 months

High infant weight increases the risk of childhood overweight, while breastfeeding may reduce the risk. However, some infants have a very high weight gain even though they are exclusively breastfed. We examined the risk of a high body mass index (BMI) and overweight in childhood for infants ≥2.5 SD above the median weight-for-age (WAZ) at age 5 months according to duration of exclusive breastfeeding (≤2, >2 to <4 or ≥4 months). The study is based on 13,401 7-year-old and 9,819 11-year-old children enrolled into the Danish National Birth Cohort (born 1997-2003). Linear and logistic regression analyses were used to examine the associations while adjusting for presumed confounders including birth weight. The results showed that infants ≥2.5 SD at 5 months, breastfed exclusively ≤2, >2 to <4 or ≥4 months had adjusted odds ratios (ORs) for overweight at age 7 at 3.67 (95% confidence interval [CI] [2.10, 6.43]), 3.42 (95% CI [2.32, 5.04]) and 3.19 (95% CI [1.90, 5.36]) respectively, when compared with infants <2.5 SD WAZ exclusively breastfed ≥4 months. The corresponding results for BMI z-scores were 0.82 (95% CI [0.60, 1.04]), 0.63 (95% CI [0.48, 0.78]) and 0.57 (95% CI [0.38, 0.77]). For the ≥2.5 SD infants, the differences in risk of overweight and BMI according to duration of exclusive breastfeeding were neither significantly different among the 7-year nor among the 11-year-old children. A high infant weight increases the odds of overweight and is associated with a higher BMI in childhood. Whereas the odds and BMI z-scores tended to be lower for those exclusively breastfed longer, the differences were not statistically significant.

Stool Saponified Fatty Acid, Behavior, Growth, and Stool Characteristics in Infants Fed a High-OPO Formula: A Randomized, Double-Blind Clinical Trial

Objective: 1,3-Dioleoyl-2-palmitoylglycerol (OPO) is an ideal structured triglyceride for infant formula, with a similar structure to human milk fat. We conducted this randomized, double-blind controlled, single-center trial to evaluate the effects of an OPO formula in infants. Study Design: One hundred seventy-four healthy term infants <14 days old were assigned to the standard formula-fed group (n = 55), high sn-2 palmitic acid (OPO) formula-fed infants (n = 58), and breastfed (BF) group (n = 61). The primary endpoint was the total saponified fatty acid content in feces at week 6 and week 12. Results: Infants from the OPO group had lower concentrations of fecal saponified fatty acids than those from the standard formula group (p < 0.0001) at week 6 and week 12. The frequencies of crying per day and per night of infants in the OPO group were significantly less than those of infants in the standard formula group (p < 0.0001). After 12 weeks of feeding, the length of infants was significantly higher in the OPO group than in the other two groups (p = 0.002). Infants in the OPO group had a significantly lower stool calcium concentration and a higher stool frequency per day than infants in the standard formula group. Conclusion: In summary, a high concentration of OPO in formula is beneficial to the growth and development of infants.

DGAT1 mutations leading to delayed chronic diarrhoea: a case report

BACKGROUND

Early-onset chronic diarrhoea often indicates a congenital disorder. Mutation in diacylglycerol o-acyltransferase 1 (DGAT1) has recently been linked to early-onset chronic diarrhoea. To date, only a few cases of DGAT1 deficiency have been reported. Diarrhoea in those cases was severe and developed in the neonatal period or within 2 months after birth.

CASE PRESENTATION

Here, we report a female patient with DGAT1 mutations with delayed-onset chronic diarrhoea. The patient had vomiting, hypoalbuminemia, hypertriglyceridemia, and failure to thrive at early infancy. Her intractable chronic diarrhoea occurred until she was 8 months of age. A compound heterozygous DGAT1 mutation was found in the patient, which was first found in the Chinese population. Her symptoms and nutrition status improved after nutritional therapy, including a fat restriction diet.

CONCLUSIONS

This case expanded our knowledge of the clinical features of patients with DGAT1 mutations. Intractable diarrhoea with delayed onset could also be a congenital disorder.

Vitamin D Deficiency in a Minnesota-Based Foster Care Population: A Cross Sectional Study

Children in foster care have complex health concerns that often interplay with their childhood experiences, environment and access to care. Studies suggest that foster care youth are at an increased risk for mental health disorders and physical disabilities. Although traditionally associated with insufficient bone development, the implications of vitamin D deficiency are broadening to encompass behavioral, neurodevelopmental, and psychological phenomena. Due to its association with diet, prenatal factors, and the prevalence of nutrition related deficiencies in foster care patients, we hypothesize that foster care patients exhibit lower levels of total 25-hydroxy vitamin D [25(OH)D] than the general pediatric population. A retrospective cross-sectional chart review of foster care patients and similar-aged non-fostered controls screened for vitamin D deficiency was conducted between January 2013 and May 2018 (n=407). Twenty-five (OH)D levels were comparable between foster care children and controls (p=0.771). A univariate analysis of risk factors within the foster care group found that higher BMI, older age, ADHD, and number of transitions was associated with decreased levels of 25(OH)D. Recognition and treatment of low 25(OH)D in foster care patients with specific risk factors may serve as an adjunct for meeting their medical and psychosocial needs.