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

Growth patterns in infants born to women with pregestational overweight/obesity supplemented with docosahexaenoic acid during pregnancy

BACKGROUND

Previous studies of maternal docosahexaenoic acid (DHA) supplementation during pregnancy have controversial and contrasting results on the short and long-term effects on early child growth. The impact of this nutritional intervention on the postnatal growth patterns in the offspring of women with pregestational overweight/obesity (PGO) also remains controversial.

OBJECTIVE

To analyze the postnatal growth patterns during the first 4 months of life in the offspring of women with PGO randomly supplemented with 800 mg/day (PGO-800) compared with normative doses of 200 mg/day (PGO-200) of DHA during pregnancy (<15 weeks of gestation until delivery).

METHODS

This study evaluated the growth patterns during the first 4 months of life of 169 infants of the women that participated in the MIGHT study (NCT02574767). We included the infants of women from the PGO-200 (n = 81) and PGO-800 group (n = 88). The growth patterns (weight, length, and head circumference) and change in z-score (World health Organization charts) were evaluated.

RESULTS

Throughout the first 4 months of life, the infants of the PGO-800 group had lower weight-for-length z-score (coef. -0.65, 95% confidence interval [CI] -1.07, -0.22, p = 0.003) and lower body mass index-for-age z-score (coef. -0.56, 95% CI -0.99, -0.12, p = 0.012) compared with the PGO-200 group adjusted by maternal body mass index, gestational weight gain, gestational age, insulin in cord blood and infant feeding (exclusive breastfed, not breastfed, and partially breastfed).

CONCLUSIONS

Maternal supplementation with DHA during pregnancy could beneficially limit the offspring's postnatal weight gain during the first 4 months of life.

Role of breastfeeding in disease prevention

Human milk provides the infant with many bioactive factors, including immunomodulating components, antimicrobials and prebiotics, which modulate the infant microbiome and immune system maturation. As a result, breastfeeding can impact infant health from infancy, through adolescence, and into adulthood. From protecting the infant from infections, to reducing the risk of obesity, type 1 diabetes and childhood leukaemia, many positive health outcomes are observed in infants receiving breastmilk. For the mother, breastfeeding protects against postpartum bleeding and depression, increases weight loss, and long-term lowers the risk of type 2 diabetes, breast and ovarian cancer, and cardiovascular diseases. Beyond infants and mothers, the wider society is also impacted because of avoidable costs relating to morbidity and mortality derived from a lack of human milk exposure. In this review, Medline was used to search for relevant articles to discuss the health benefits of breastfeeding and its societal impact before exploring future recommendations to enhance our understanding of the mechanisms behind breastfeeding's positive effects and promote breastfeeding on a global scale.

The relationship between mothers' body composition and anthropometric characteristics of baby and breast milk nutrient content: A cross-sectional study

BACKGROUND

The composition and amount of breast milk is affected by factors such as the duration and frequency of breastfeeding, the time between two breastfeeding sessions, the effectiveness of breastfeeding, breastfeeding technique, genetic characteristics of the mother and diet. Breast milk macronutrients are provided by milk synthesized in lactocytes, mother's diet and maternal stores.

RESEARCH AIM

This study was conducted to investigate the relationship between the body composition of mothers and the anthropometric characteristics of the baby and the nutritional content of breast milk.

METHOD

The descriptive study was conducted between March and November 2023 in a hospital in a low socioeconomic neighbourhood in Turkey. The study sample consisted of 96 mothers and ibabies. Anthropometric measurements of mothers and babies and the nutrient content of breast milk were evaluated on the first postpartum day, Days 5 and 15. Breast milk macronutrient content was analyzed by Miris milk analyzer and body composition of mothers was analyzed by TANITA BC 730.

RESULTS

From the weight and body composition of the mothers in the study group; a positive correlation was found between body fat, muscle and water ratio, and breast milk carnonhydrate and protein (p < 0.05). There was no correlation between the gestational age of the baby and the content of breast milk (p > 0.05). A positive correlation was found between the weight and height of the babies and the macronutrients of breast milk (p < 0.05).

CONCLUSION

As the weight of mothers increases, breast milk protein and carbohydrate levels increase. As breast milk macronutrients increase, babies' weight and height increase.

Is Maternal Body Weight or Composition Associated with Onset of Lactogenesis II, Human Milk Production, or Infant Consumption of Mother's Own Milk? A Systematic Review and Meta-Analysis

Maternal adiposity impacts lactation performance, but the pathways are unclear. We conducted a systematic review to understand whether maternal adiposity (body mass index [BMI] or percentage fat mass) is associated with onset of lactogenesis II (copious milk; hours), human milk production (expressed volume/24 h), and infant consumption of mother's own milk (volume/24 h). We used random-effects standard meta-analyses to compare the relative risk (RR) of delayed lactogenesis II (>72 h) between mothers classified as underweight (BMI <18.5 kg/m2), healthy weight (BMI, 18.5-24.9 kg/m2), and overweight/obese (BMI ≥25 kg/m2) and random-effects meta-regressions to examine associations with hours to lactogenesis II and infant milk consumption. The certainty of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation approach. We included 122 articles. Mothers with underweight (RR: 0.64; 95% CI: 0.49, 0.83; I2 = 39.48%; 8 articles/data points) or healthy weight status (RR: 0.67; 95% CI: 0.57, 0.79; I2 = 70.91%; 15 articles/data points) were less likely to experience delayed lactogenesis II than mothers with overweight/obesity. We found no association between maternal BMI and time to onset of lactogenesis II (β: 1.45 h; 95% CI: -3.19, 6.09 h; P = 0.52, I2 = 0.00%; 8 articles, 17 data points). Due to limited data, we narratively reviewed articles examining BMI or percentage fat mass and milk production (n = 6); half reported an inverse association and half no association. We found no association between maternal BMI (β: 6.23 mL; 95% CI: -11.26, 23.72 mL; P = 0.48, I2 = 47.23%; 58 articles, 75 data points) or percentage fat mass (β: 7.82 mL; 95% CI: -1.66, 17.29 mL; P = 0.10, I2 = 28.55%; 30 articles, 41 data points) and infant milk consumption. The certainty of evidence for all outcomes was very low. In conclusion, mothers with overweight/obesity may be at risk of delayed lactogenesis II. The available data do not support an association with infant milk consumption, but the included studies do not adequately represent mothers with obesity. This study was registered in PROSPERO as 285344.

Human Milk Composition Is Associated with Maternal Body Mass Index in a Cross-Sectional, Untargeted Metabolomics Analysis of Human Milk from Guatemalan Mothers

Background

Maternal overweight and obesity has been associated with poor lactation performance including delayed lactogenesis and reduced duration. However, the effect on human milk composition is less well understood.

Objectives

We evaluated the relationship of maternal BMI on the human milk metabolome among Guatemalan mothers.

Methods

We used data from 75 Guatemalan mothers who participated in the Household Air Pollution Intervention Network trial. Maternal BMI was measured between 9 and <20 weeks of gestation. Milk samples were collected at a single time point using aseptic collection from one breast at 6 mo postpartum and analyzed using high-resolution mass spectrometry. A cross-sectional untargeted high-resolution metabolomics analysis was performed by coupling hydrophilic interaction liquid chromatography (HILIC) and reverse phase C18 chromatography with mass spectrometry. Metabolic features associated with maternal BMI were determined by a metabolome-wide association study (MWAS), adjusting for baseline maternal age, education, and dietary diversity, and perturbations in metabolic pathways were identified by pathway enrichment analysis.

Results

The mean age of participants at baseline was 23.62 ± 3.81 y, and mean BMI was 24.27 ± 4.22 kg/m2. Of the total metabolic features detected by HILIC column (19,199 features) and by C18 column (11,594 features), BMI was associated with 1026 HILIC and 500 C18 features. Enriched pathways represented amino acid metabolism, galactose metabolism, and xenobiotic metabolic metabolism. However, no significant features were identified after adjusting for multiple comparisons using the Benjamini-Hochberg false discovery rate procedure (FDRBH < 0.2).

Conclusions

Findings from this untargeted MWAS indicate that maternal BMI is associated with metabolic perturbations of galactose metabolism, xenobiotic metabolism, and xenobiotic metabolism by cytochrome p450 and biosynthesis of amino acid pathways. Significant metabolic pathway alterations detected in human milk were associated with energy metabolism-related pathways including carbohydrate and amino acid metabolism.This trial was registered at clinicaltrials.gov as NCT02944682.

The effect of extra virgin olive oil (EVOO) on fat mass and fat-free mass for breastfeeding mothers (0-24 months) in Makassar City, Indonesia

BACKGROUND

Extra Virgin Olive Oil (EVOO) is a fat source classified as monounsaturated fatty acid. Previous studies have shown that 47.5% of breastfeeding mothers have less fat intake when compared to the Adequacy of Nutrition Rate (RDA). EVOO consumption can improve the composition of breast milk. However, no research has been found regarding the body composition of breastfeeding mothers after consuming EVOO. This study aims to determine the effect of EVOO on the body composition of breastfeeding mothers 0-24 months.

MATERIALS AND METHODS

The study was conducted at the Sudiang Raya and Tamalanrea Health Centers in Makassar City with a randomized clinical trial design from January to February 2023. The sample was breastfeeding mothers 0-24 months divided into the intervention group (EVOO and Nutrition Education, n = 17) and the control (Nutrition Education, n = 17). Instruments with Bioelectrical Impedence Analysis tools. Data analysis using t-test.

RESULTS

The sample is breastfeeding mothers aged between ≤19 and >35 years. The results of the analysis showed that the average pre-post test, % fat mass (FM) P = 0.426 and % fat free mass (FFM) P = 0.508 (P > 0.05), meant that there was no significant difference. Between the two groups there was no significant difference at the end of the study, %FM P = 0.469 and %FFM P = 0.529 (P > 0.05).

CONCLUSIONS

In the intervention group that was given EVOO, it was possible to maintain%FM and%FFM in the normal percentage range, while in the control group, there was a decrease from the normal to less/low range.

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.

Undernutrition among exclusive breastfeeding mothers and its associated factors in Southwest Ethiopia: A community-based study

BACKGROUND

An exclusive breastfeeding period is a time when the infant's feeding depends on only breast milk. Inadequate maternal nutrition during this period could lead to insufficient infant feeding, which can further lead to childhood undernutrition and developmental restrictions. Evidently, the burden of maternal undernutrition was higher in resource-limited countries, including Ethiopia.

OBJECTIVES

This study aimed to assess the proportion of undernutrition among exclusive breastfeeding mothers and its associated factors in Southwest Ethiopia.

DESIGN

The study used a community-based cross-sectional design.

METHODS

The study was conducted among 442 nursing mothers from 10 to 30 June 2022. The participants were selected using multistage sampling techniques. An interviewer-administered structured questionnaire was used to collect information. Statistical software EpiData version 3.1 and SPSS version 20 were used for data entry and analysis, respectively. The factors associated with undernutrition were identified using a binary logistic regression analysis. In the bivariable analysis, a p-value of less than 0.25 was used to include the variable in the multivariable analysis, whereas p-value less than 0.05 was an odds ratio used to declare an independent association at a 95% confidence interval.

RESULTS

The proportion of undernutrition among the participants was found to be 24.8% in the study area. Poor intake of extra meals (adjusted odds ratio = 2.104; 95% confidence interval: 1.208, 3.664), poor dietary diversity habits (adjusted odds ratio = 3.605; 95% confidence interval: 2.112, 6.153), a lack of nutrition information (adjusted odds ratio = 1.853; 95% confidence interval: 1.070, 3.212), and household food insecurity (adjusted odds ratio = 4.424; 95% confidence interval: 2.639, 7.417) were identified as factors enhancing undernutrition among exclusive breastfeeding mothers in the area.

CONCLUSION

A quarter of exclusive breastfeeding mothers were undernourished in the area. Poor dietary diversity habits, poor intake of extra meals, a lack of nutrition information, and household food insecurity were found to be the factors determining undernutrition. Hence, it is important to reinforce nutrition intervention programs, including maternal nutrition education and counseling.

Comparative proteomic analysis of human milk fat globules and paired membranes and mouse milk fat globules identifies core cellular systems contributing to mammary lipid trafficking and secretion

Introduction: Human milk delivers critical nutritional and immunological support to human infants. Milk fat globules (MFGs) and their associated membranes (MFGMs) contain the majority of milk lipids and many bioactive components that contribute to neonatal development and health, yet their compositions have not been fully defined, and the mechanisms responsible for formation of these structures remain incompletely understood. Methods: In this study, we used untargeted mass spectrometry to quantitatively profile the protein compositions of freshly obtained MFGs and their paired, physically separated MFGM fractions from 13 human milk samples. We also quantitatively profiled the MFG protein compositions of 9 pooled milk samples from 18 lactating mouse dams. Results: We identified 2,453 proteins and 2,795 proteins in the majority of human MFG and MFGM samples, respectively, and 1,577 proteins in mouse MFGs. Using paired analyses of protein abundance in MFGMs compared to MFGs (MFGM-MFG; 1% FDR), we identified 699 proteins that were more highly abundant in MFGMs (MFGM-enriched), and 201 proteins that were less abundant in MFGMs (cytoplasmic). MFGM-enriched proteins comprised membrane systems (apical plasma membrane and multiple vesicular membranes) hypothesized to be responsible for lipid and protein secretion and components of membrane transport and signaling systems. Cytoplasmic proteins included ribosomal and proteasomal systems. Comparing abundance between human and mouse MFGs, we found a positive correlation (R 2 = 0.44, p < 0.0001) in the relative abundances of 1,279 proteins that were found in common across species. Discussion: Comparative pathway enrichment analyses between human and mouse samples reveal similarities in membrane trafficking and signaling pathways involved in milk fat secretion and identify potentially novel immunological components of MFGs. Our results advance knowledge of the composition and relative quantities of proteins in human and mouse MFGs in greater detail, provide a quantitative profile of specifically enriched human MFGM proteins, and identify core cellular systems involved in milk lipid secretion.

Changes in Mature Human Milk Macronutrient Composition over 45 years in an Urban Population in Indonesia

BACKGROUND

With improvement in a population's welfare, its food consumption patterns may change, including those of nursing mothers. This, in turn, could influence their human milk composition.

RESEARCH AIM

To investigate the secular trend in macronutrient composition of mature human milk from mothers of healthy, full-term infants in urban populations in Indonesia from 1974 and 2019.

METHOD

We compared the macronutrient composition of mature human milk of healthy full-term infants from 1974 and 2019. The data from 2019 used the Human Milk Analyzer MIRIS to quantify the milk's carbohydrate, fat, and protein content, while the historical data used methods available at that time, that is, methods described by Benedict, Gerber and Kjeldahl, respectively.

RESULTS

There were no significant differences in carbohydrate, protein and fat content across categories of maternal nutritional status in the respective periods. However, the fat content of human milk from 2019 was significantly higher than that of 1974 (4.7 g/dl, SD = 1.7 g/dl vs. 3.3 g/dl, SD = 1.1 g/dl; p < 0.001), while its carbohydrate content was significantly lower (6.2 g/dl, SD = 2.1 g/dl vs. 7.1 g/dl, SD = 0.2 g/dl; p < 0.001). There was no difference in the protein content between the two periods (1.4 g/dl, SD = 0.5 g/dl vs. 1.6 g/dl, SD = 0.3 g/dl; p = 0.491).

CONCLUSION

The mature human milk from 2019 has a higher fat and total energy content but lower carbohydrate content than those observed 4 decades ago. The protein content remained the same.

Promoting and supporting breastfeeding in a protracted emergency setting-Caregivers' and health workers' perceptions from North-East Nigeria

Background

Breastfeeding (BF) should be protected, promoted, and supported for all infants in humanitarian settings. The re-establishment of exclusive BF is also a central part of the management of acutely malnourished infants under 6 months (<6 m). Médecins Sans Frontières (MSF) runs a nutrition project in Maiduguri, a protracted emergency setting in North-East Nigeria. This study aimed to explore caregivers' (CGs) and health workers' (HWs) perceptions of BF practice, promotion, and support among CGs with infants <6 m in this setting.

Methods

We conducted a qualitative study using in-depth interviews and focus group discussions combined with non-participant observations. Participants included CGs of young infants enrolled in MSF nutritional programs or who attended health promotion activities in a displacement camp. MSF HWs were involved at different levels in BF promotion and support. Data were collected involving a local translator and analyzed using reflexive thematic analysis directly from audio recordings.

Results

Participants described how feeding practices are shaped by family, community, and traditional beliefs. The perception of breastmilk insufficiency was common and led to early supplementary feeding with inexpensive but unsuitable products. Participants often linked insufficient breastmilk production with poor maternal nutrition and stress, in a context shaped by conflict and food insecurity. BF promotion was generally well received but could be improved if tailored to address specific barriers to exclusive BF. Interviewed CGs positively valued BF support received as part of the comprehensive treatment for infant malnutrition. One of the main challenges identified was the length of stay at the facility. Some participants perceived that improvements in BF were at risk of being lost after discharge if CGs lacked an enabling environment for BF.

Conclusion

This study corroborates the strong influence of household and contextual factors on the practice, promotion, and support of BF. Despite identified challenges, the provision of BF support contributes to improvements in BF practice and was positively perceived by CGs in the studied setting. Greater attention should be directed toward providing support and follow-up for infants <6 m and their CGs in the community.

The Role of Protein Intake on the Total Milk Protein in Lead-Exposed Lactating Mothers

Protein is an essential macronutrient for the growth and development of infants. Protein levels in lactating mothers are dynamic and influenced by various factors, particularly the environment and maternal characteristics. Therefore, this study aimed to evaluate the complex correlation between maternal blood lead levels (BLLs), maternal diet, and total milk protein. The Kruskal-Wallis test was used to compare total milk protein in the three groups of lead exposure, while Spearman's correlation was used to assess the correlation between maternal diet, BLLs, and total milk protein. The multivariate analysis used multiple linear regression. The results showed that the median of maternal BLLs and total milk protein were 3.3 µg/dL and 1.07 g/dL, respectively. Maternal protein intake and current BMI had a positive correlation with total milk protein, while BLLs had a negative correlation. BLLs ≥ 5 μg/dL had the most significant impact on reducing the total milk protein (p = 0.032). However, increasing maternal protein intake can effectively maintain total milk protein levels in mothers with BLLs under 5 μg/dL (p < 0.001). It is crucial to measure BLLs in lactating mothers residing in areas exposed to lead because high maternal protein intake can only maintain total milk protein levels when the BLLs are <5 μg/dL.

Ecologies, synergies, and biological systems shaping human milk composition-a report from "Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN)" Working Group 2

Human milk is universally recognized as the preferred food for infants during the first 6 mo of life because it provides not only essential and conditionally essential nutrients in necessary amounts but also other biologically active components that are instrumental in protecting, communicating important information to support, and promoting optimal development and growth in infants. Despite decades of research, however, the multifaceted impacts of human milk consumption on infant health are far from understood on a biological or physiological basis. Reasons for this lack of comprehensive knowledge of human milk functions are numerous, including the fact that milk components tend to be studied in isolation, although there is reason to believe that they interact. In addition, milk composition can vary greatly within an individual as well as within and among populations. The objective of this working group within the Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN) Project was to provide an overview of human milk composition, factors impacting its variation, and how its components may function to coordinately nourish, protect, and communicate complex information to the recipient infant. Moreover, we discuss the ways whereby milk components might interact such that the benefits of an intact milk matrix are greater than the sum of its parts. We then apply several examples to illustrate how milk is better thought of as a biological system rather than a more simplistic "mixture" of independent components to synergistically support optimal infant health.

Maternal BMI in the preconception period, and association with child zBMI growth rates

BACKGROUND

Elevated body mass index (BMI) and rapid growth in early childhood are important predictors of obesity risk. The association between maternal preconception BMI and child growth rates is unclear.

OBJECTIVES

To assess the association between measured maternal preconception BMI and child age- and sex- standardized WHO BMI z-score (zBMI) growth rates and mean zBMI, in children aged 0-10 years old.

METHODS

A longitudinal cohort study was conducted with children (n = 499) enrolled in The Applied Research Group for Kids (TARGet Kids!) primary care practice-based research cohort. Maternal BMI was measured during the preconception period, defined as the 2 years prior to pregnancy. Repeated measures of child weight and height were obtained between 0 and 10 years of age. Linear mixed models were used to evaluate the association between maternal BMI and child zBMI growth rates and mean zBMI.

RESULTS

Maternal preconception BMI was associated with child zBMI growth rate during some growth periods, with the strongest association from age 0 to 4 months; a 5 kg/m2 higher maternal BMI was associated with 0.031 zBMI SD unit/mo higher growth rate (p = 0.004), and 0.186 SD unit higher mean child zBMI (p = 0.0002).

CONCLUSIONS

Maternal preconception BMI was associated with growth rate and mean zBMI in early childhood. The preconception period may be an important target for health interventions to promote healthy child growth rate and weight outcomes.

Maternal nutritional status and milk volume and composition in India: an observational study

BACKGROUND

Human milk provides essential nutrition for infants, and its benefits are well established. We lack data on the influence of maternal nutritional status on milk volume and composition in low-middle income countries.

OBJECTIVE

We aimed to 1) assess lactation performance (human milk volume, macronutrient composition, and infant energy intake) in Indian females and 2) examine the associations between maternal anthropometry (BMI, percentage body fat) and lactation performance.

METHODS

We conducted an observational study among 232 mother-infant dyads, 2 to 4 mo postpartum in Haryana, India. We used deuterium oxide dose-to-mother technique to measure milk volume and maternal percentage body fat and collected human milk samples to determine macronutrient and energy concentrations. Adjusted multiple linear regression models were used to examine the associations between maternal anthropometry and lactation performance.

RESULTS

The mean BMI and percentage body fat of mothers were 21.7 ± 3.6 kg/m² and 29.5 ± 7.7, respectively. Milk volume and macronutrient composition were similar to the reference values (means ± standard deviations: milk volume, 724 ± 184 mL/d; median (25th, 75th percentile); protein, 9.9 (8.3, 11.7) g/L; fat, 41.0 ± 15.2 g/L; energy density, 0.71 ± 0.14 kcal/g; lactose, 65.5 (55.3, 71.3) g/L). Maternal BMI and percentage body fat were not significantly associated with macronutrient composition. Both maternal BMI and percentage body fat were negatively associated with milk volume (-7.0, 95% CI: -12.4, -1.6 mL/d; -3.5, 95% CI: -6.0, -1.1mL/d, respectively) but there were no effects on the total energy intake of infants after adjusting for covariates.

CONCLUSION

Most mothers had a normal BMI and milk of similar composition and volume to reference values. Future work in populations with a greater burden of underweight and/or obesity are needed to examine the underlying mechanisms between maternal body composition and milk volume. This trial was registered at The Clinical Trials Registry- India as CTRI/2017/01/007636.

Maternal Diet Influences Human Milk Protein Concentration and Adipose Tissue Marker

(1) Background: Adequate protein intake plays an essential role in growth and neurodevelopment, especially in preterm infants. We investigated the effects of maternal diet and body mass index (BMI) on human milk (HM) composition. (2) Methods: HM samples were obtained from 136 lactating mothers (BMI: 18.0−36.7 kg/m2), of which 93% gave birth to preterm infants. Macronutrient content in HM was measured by mid-infrared transmission spectroscopy. Leptin and adiponectin were analyzed using appropriate ELISAs. Maternal diet was determined by 24-h recall. (3) Results: Significant positive associations were found between protein, fat, carbohydrate and energy intake, and levels of corresponding macronutrients in HM, especially in protein concentrations (p < 0.001). An increased protein intake was positively correlated with adiponectin (p < 0.001) and leptin (p = 0.035) in HM. Maternal BMI was positively associated with a higher protein level in HM (p < 0.05), as well as with a higher dietary protein intake (p < 0.05). (4) Conclusions: Knowledge of maternal diet and BMI impacting HM composition is essential to optimize the feeding of newborn infants. This is especially relevant in the nutritional management of preterm infants; it can be utilized in approaches to improve growth rates and the appropriate development of infants and to prevent obesity.

Human milk pH is associated with fortification, postpartum day, and maternal dietary intake in preterm mother-infant dyads

OBJECTIVE

To compare pH of human milk types (mother's own milk (MOM), pasteurized donor human milk (PDHM), fortified MOM, and fortified PDHM) fed to preterm infants.

STUDY DESIGN

This observational study consisted of 63 mother-infant dyads < 34 weeks gestation. Human milk samples (n = 245), along with maternal factors, were collected for pH analysis. pH of MOM was analyzed over the course of lactation accounting for fortification status, postpartum day, and storage conditions.

RESULTS

Mean pH of MOM was slightly acidic at 6.60 ± 0.28, which was significantly higher (p < 0.05) than other milk types. pH of MOM varied by fortification, postpartum day, and maternal vegetable/fiber intake. There was a significant interaction between fortification status and postpartum day; pH of MOM decreased over time, while pH of fortified MOM increased over time.

CONCLUSION

pH of human milk varied by type. pH of MOM was significantly associated with fortification status, postpartum day, and maternal vegetable/fiber intake.

Association between Adherence to the Healthy Food Pyramid and Breast Milk Fatty Acids in the First Month of Lactation

In lactating women, breast milk (BM) fatty acids may come from the diet or stored adipose tissue. Our objective was to evaluate the influence of the adherence to the healthy food pyramid (HFP), the dietary pattern in the Mediterranean region, and the maternal body composition on the BM fatty acids pattern. Fifty breastfeeding women answered a socioeconomic survey and the adherence to the HFP questionnaire (AP-Q). In addition, they provided a BM sample at 7 ± 1, 14 ± 1, and 28 ± 1 days postpartum. The body's composition was analyzed at days 7 and 28 by bioimpedance. The BM fatty acids were analyzed by gas chromatography-mass spectroscopy. We found a negative association between the consumption of olive oil and the BM palmitic acid levels (β = -3.19 ± 1.40; p = 0.030), and the intake of cereals and legumes was positively associated with the BM saturated fatty acids (β = 11.48 ± 3.87; p = 0.005). The intake of proteins and vegetables was positively associated with the omega-3 fatty acids and negatively with the omega-6:omega-3 ratio in BM. A negative association between the maternal age (β = -0.43 ± 0.11; p = 0.001) and the α-linolenic acid (ALA) levels was observed, being overall AP-Q positively associated with the ALA levels (β = 0.39 ± 0.15; p = 0.016). Physical activity reduced both the omega-3 and omega-6 fatty acids in BM. Diet had a larger influence than the maternal body's composition on BM fatty acids during the first month of lactation, demonstrating a better adherence to the HFP and positively impacting on the omega-3 content in BM, a fact that is modulated by one's maternal age.

Milk Exosomal microRNAs: Postnatal Promoters of β Cell Proliferation but Potential Inducers of β Cell De-Differentiation in Adult Life

Pancreatic β cell expansion and functional maturation during the birth-to-weaning period is driven by epigenetic programs primarily triggered by growth factors, hormones, and nutrients provided by human milk. As shown recently, exosomes derived from various origins interact with β cells. This review elucidates the potential role of milk-derived exosomes (MEX) and their microRNAs (miRs) on pancreatic β cell programming during the postnatal period of lactation as well as during continuous cow milk exposure of adult humans to bovine MEX. Mechanistic evidence suggests that MEX miRs stimulate mTORC1/c-MYC-dependent postnatal β cell proliferation and glycolysis, but attenuate β cell differentiation, mitochondrial function, and insulin synthesis and secretion. MEX miR content is negatively affected by maternal obesity, gestational diabetes, psychological stress, caesarean delivery, and is completely absent in infant formula. Weaning-related disappearance of MEX miRs may be the critical event switching β cells from proliferation to TGF-β/AMPK-mediated cell differentiation, whereas continued exposure of adult humans to bovine MEX miRs via intake of pasteurized cow milk may reverse β cell differentiation, promoting β cell de-differentiation. Whereas MEX miR signaling supports postnatal β cell proliferation (diabetes prevention), persistent bovine MEX exposure after the lactation period may de-differentiate β cells back to the postnatal phenotype (diabetes induction).

Perspective: Human Milk Composition and Related Data for National Health and Nutrition Monitoring and Related Research

National health and nutrition monitoring is an important federal effort in the United States and Canada, and the basis for many of their nutrition and health policies. Understanding of child exposures through human milk (HM) remains out of reach due to lack of current and representative data on HM's composition and intake volume. This article provides an overview of the current national health and nutrition monitoring activities for HM-fed children, HM composition (HMC) and volume data used for exposure assessment, categories of potential measures in HM, and associated variability factors. In this Perspective, we advocate for a framework for collection and reporting of HMC data for national health and nutrition monitoring and programmatic needs, including a shared vision for a publicly available Human Milk Composition Data Repository (HMCD-R) to include essential metadata associated with HMC. HMCD-R can provide a central, integrated platform for researchers and public health officials for compiling, evaluating, and sharing HMC data. The compiled compositional and metadata in HMCD-R would provide pertinent measures of central tendency and variability and allow use of modeling techniques to approximate compositional profiles for subgroups, providing more accurate exposure assessments for purposes of monitoring and surveillance. HMC and related metadata could facilitate understanding the complexity and variability of HM composition, provide crucial data for assessment of infant and maternal nutritional needs, and inform public health policies, food and nutrition programs, and clinical practice guidelines.

Timing and pattern of growth faltering in children up-to 18 months of age and the associated feeding practices in an urban setting of Sri Lanka

BACKGROUND

Growth faltering is commonly encountered in breastfed infants during 4-6 months of age in low socioeconomic communities. The objective of this study was to describe the changes of growth indices with age, timing of growth faltering and its association with the feeding practices in children up-to 18 months of age.

METHODS

A cross sectional descriptive study was conducted in 254 children aged 12 and 18 months attending an immunization clinic. Data on growth were extracted from the Child Health Development Record. Weight and length were measured using standard methods. Feeding practices were assessed using interviewer-administered questionnaire. A drop of > 0.25 in weight-for-age Standard Deviation Score (SDS) from birth SDS was defined as weight faltering.

RESULTS

Weight faltering occurred at some point in 64.2% (n = 163) during first 18 months of life, and 78.5% of whom, had the onset ≤ 4 months of age. Majority (76.6%, n = 98) with weight for age faltering by 4 months remained so at 12 months (p = 0.497), while 29.7% (n = 38) had a weight-for-length below-2SD (p < 0.001). Prevalence of weight faltering was 50.4%, 46.1%, 48.4% and 48% at 4, 6, 9 and 12 months respectively. Exclusive breastfeeding was given at least until 4 months in 88% (n = 223) and up to 6 months in 60% (n = 153) while 92.9% (n = 236) were breastfed at 12 months, with 38.2% (n = 97) were breastfed on demand after six months. Complementary feeding (CF) was started before 6 months in 40.6% (n = 52) with early weight faltering, but only 20.3% received it with proper consistency. Breastfeeding throughout the night was significantly associated with current weight-for-length being < -1SD (OR = 1.89, CI, 1.04-3.45; p = 0.037).

CONCLUSIONS

Early growth faltering was found in this population with high exclusive breastfeeding rates and persisting growth faltering was associated with poor feeding practices. Therefore, timely individualized interventions need to be taken to improve long term growth.

Investigation of the Effect of Human Milk Expression Techniques on Milk Content: A Systematic Review

BACKGROUND

If the mother and infant cannot meet after birth, it is recommended to express milk and give it to the infant. There was evidence indicating that there might be decrease in essential nutrient values in human milk content depending on the expression technique in literature. The goal of this systematic review was to investigate the effect of human milk expression techniques on the macronutrient milk content and establish an evidence base for future studies.

METHODS

Studies investigating the effect of human milk expression techniques on milk content were reviewed without year limitations. A literature review was conducted in six electronic databases (MEDLINE, Web of Science, PubMed, ScienceDirect, CINAHL and Cochrane) until 30 May 2021, using the keywords of breast milk expression techniques, milk content and breast milk pumping.

RESULTS

From 258 articles initially screened, we included 6 articles in the systematic review. The fat, protein and lactose content of human milk was analyzed in the studies reviewed. It was concluded that there was no significant effect on the protein (9.7-9.8 g/dl and 2.1-2.1 g/dl, respectively) and lactose (6.50-6.53% and 6.1-6.1 g/dl, respectively) content of milk. However, the fat (58.30, 48.81g/l; 2.6-2.2 g/dl) content was affected.

CONCLUSIONS

This study investigated the effect of milk expression techniques on the macronutrient content of human milk, and it was concluded that there was no significant effect on the protein and carbohydrate content of milk. However, the fat content was affected. Limitation of this study is that some factors that might affect the content of human milk were not standardized sufficiently in the included studies.

Determinants of fatty acid content and composition of human milk fed to infants born weighing <1250 g

BACKGROUND

Infants born at very low birth weight (VLBW) are vulnerable to deficits in fatty acids (FAs) but little is known of factors that influence the intakes or composition of their human milk feeds.

OBJECTIVES

We aimed to identify sources of variability in the fat composition of human milk fed to VLBW infants and examine the impact of milk source (mother's own or donor) on fat and FA intakes.

METHODS

Serial samples of mother's milk (n = 476) and donor milk (n = 53) fed to infants born weighing <1250 g (n = 114 infants from 100 mothers) were collected [Optimizing Mothers' Milk for Preterm Infants (OptiMoM) randomized clinical trial]. Fat and FA were analyzed using a mid-infrared human milk analyzer and GC with flame ionization detection.

RESULTS

At full enteral feeding, donor milk is estimated to provide 1.3 g · kg-1 · d-1 less total fat than mature mother's milk (recommended intake: 4.8 g · kg-1 · d-1), and 5-9 mg · kg-1 · d-1 less DHA (22:6n-3) and arachidonic acid (20:4n-6) (estimated average requirement: 55-60 and 35-45 mg · kg-1 · d-1, respectively) than colostrum or transitional milk. Similar deficits were observed in measured intakes of a subset of OptiMoM infants. In multivariable-adjusted models, maternal ethnicity had medium to large [≥0.5 SD score (SDS)] effects on DHA, SFAs, and MUFAs. Mothers with prepregnancy BMI in overweight and obese categories had higher milk total fat (β: 0.35; 95% CI: 0.10, 0.61 and β: 0.46; 95% CI: 0.16, 0.77 SDS, respectively). Those with BMI ≥30 in addition had higher proportions of SFAs (β: 0.61; 95% CI: 0.33, 0.89 SDS) and lower DHA (β: -0.54; 95% CI: -0.89, -0.20 SDS). Other factors, such as gestational age and income, were also associated with FA composition.

CONCLUSIONS

The fat and FA content of human milk fed to VLBW infants is variable. Care must be taken to ensure fat and FA intakes meet recommendations, particularly when feeding a high proportion of donor milk.This trial was registered at clinicaltrials.gov as NCT02137473.

The clinical impact of maternal weight on offspring health: lights and shadows in breast milk metabolome

INTRODUCTION

Pre-pregnancy overweight and obesity, depending on maternal nutrition and metabolic state, can influence fetal, neonatal and long-term offspring health, regarding cardio-metabolic, respiratory, immunological and cognitive outcomes. Thus, maternal weight can act, through mechanisms that are not full understood, on the physiology and metabolism of some fetal organs and tissues, to adapt themselves to the intrauterine environment and nutritional reserves. These effects could occur by modulating gene expression, neonatal microbiome, and through breastfeeding.

AREAS COVERED

In this paper, we investigated the potential effects of metabolites found altered in breast milk (BM) of overweight/obese mothers, through an extensive review of metabolomics studies, and the potential short- and long-term clinical effects in the offspring, especially regarding overweight, glucose homeostasis, insulin resistance, oxidative stress, infections, immune processes, and neurodevelopment.

EXPERT OPINION

Metabolomics seems the ideal tool to investigate BM variation depending on maternal or fetal/neonatal factors. In particular, BM metabolome alterations according to maternal conditions were recently pointed out in cases of gestational diabetes, preeclampsia, intrauterine growth restriction and maternal overweight/obesity. In our opinion, even if BM is the food of choice in neonatal nutrition, the deepest comprehension of its composition in overweight/obese mothers could allow targeted supplementation, to improve offspring health and metabolic homeostasis.