Modulação e composição de ácidos graxos do leite humano

Determination of the Fatty Acid Profile and Lipid Quality Indices in Selected Infant Formulas

The quality of fat in infant milk is determined by the fatty acid profile and selected indices describing nutritional value. The aim of this study was to analyze the fatty acid profile and lipid quality indices of infant formulas and compare these data with breast milk. The study material included seven types of cow's milk-based follow-on infant formulas and samples of mature breast milk. The determination of fatty acids was performed using the gas chromatography (GC) technique. Lipid quality indices were calculated based on the relevant equations. Infant formulas contained more medium-chain fatty acids (MCFAs) and oleic acid. Moreover, they contained more than 30% more linoleic acid and more than twice as much α-linolenic acid and docosahexaenoic acid. In contrast, significant amounts of trans fatty acids (TFAs) were noted in breast milk, while infant formulas contained trace amounts. Infant formulas were characterized by a lower AI (Index of Atherogenicity) (0.49-0.98) and TI (Index of Thrombogenicity) (0.48-0.60) and a higher H/H (hypocholesterolemic/hypercholesterolemic) ratio (1.93-2.30) compared with breast milk (1.47, 1.60, and 1.21, respectively). The composition of infant formulas depended on the type of fat added at the production stage and differed significantly from breast milk, particularly in terms of polyunsaturated fatty acids and lipid quality indices.

Nutritional composition of human milk and its association with maternal and perinatal factors

OBJECTIVE

The objective of this study was to evaluate the influence of maternal and perinatal factors on the nutritional composition of human milk.

METHODS

A cross-sectional study was conducted between November 2018 and January 2020, with 181 donors selected in Tertiary Health Units of the Unified Health System - from one collection station and five Human Milk Banks. Data were collected through a standardized questionnaire. To be fit to be a donor in a Human Milk Banks and produce mature milk were the eligibility criteria to participate in the study. We excluded milk samples with Dornic acidity above 8° D. The dependent variables were the macronutrients of human milk (i.e., carbohydrates, proteins, lipids, and total energy), that were analyzed using spectroscopy with the Miris Human Milk Analyzer™. The maternal and perinatal factors were the independent variables.

RESULTS

Women with pre-gestational obesity and gestational weight gain above the recommendation showed a lower protein concentration compared to eutrophic women (median=0.8, interquartile range (IQR): 0.7-0.9 vs. median=0.8, and IQR: 0.8-1.0) and those with adequate gestational weight gain (median=0.8, IQR: 0.7-0.9 vs. median=0.9, and IQR: 0.8-1.0), respectively. The other analyzed factors (i.e., maternal habits, comorbidities, and perinatal factors) were not associated with the nutritional composition of human milk.

CONCLUSIONS

The assessment of factors associated with the nutritional composition of human milk is extremely important to assist postpartum care. Pre-gestational obesity and inadequate gestational weight gain were the only factors statistically associated with the nutritional composition of human milk as they impacted its protein content.

Effects of dietary PUFA patterns and FADS genotype on breast milk PUFAs in Chinese lactating mothers

BACKGROUND

Breastfeeding affects the growth and development of infants, and polyunsaturated fatty acids (PUFAs) play a crucial role in this process. To explore the factors influencing the PUFA concentration in breast milk, we conducted research on two aspects: dietary fatty acid patterns and single nucleotide polymorphisms (SNPs) in maternal fatty acid desaturase genes.

METHODS

Three hundred seventy Chinese Han lactating mothers were recruited. A dietary semi-quantitative food frequency questionnaire (FFQ) was used to investigate the dietary intake of lactating mothers from 22 to 25 days postpartum for 1 year. Meanwhile, breast milk samples were collected from the participants and tested for the concentrations of 8 PUFAs and 10 SNP genotypes. We sought to determine the effect of dietary PUFA patterns and SNPs on breast milk PUFAs. We used SPSS 24.0 statistical software for data analysis. Statistical tests were all bilateral tests, with P < 0.05 as statistically significant.

RESULTS

Under the same dietary background, PUFA contents in breast milk expressed by most major allele homozygote mothers tended to be higher than that expressed by their counterparts who carried minor allele genes. Moreover, under the same gene background, PUFA contents in breast milk expressed by the mother's intake of essential PUFA pattern tended to be higher than that expressed by their counterparts who took the other two kinds of dietary.

CONCLUSIONS

Our study suggests that different genotypes and dietary PUFA patterns affect PUFA levels in breast milk. We recommend that lactating mothers consume enough essential fatty acids to ensure that their infants ingest sufficient PUFAs.

Profiles of total and sn-2 fatty acid of human mature milk and their correlated factors: A cross-sectional study in China

Fatty acid (FA) in breast milk is beneficial to the growth and neurodevelopment of infants. However, the structure profiles of breast milk FAs and the influencing factors which are crucial for normal function have not been fully elucidated. This study aimed to characterize the profiles of total and sn-2 FAs in human mature milk based on two representative urban areas in China and explore potential sociodemographic determinants. Mothers (n = 70) at 40–100 d postpartum from Beijing and Danyang were recruited according to unified inclusion and exclusion criteria. Total and sn-2 FA compositions were examined by gas chromatography and quantified. Using the Spearman correlation and multiple regression model, we found that the location and maternal education level were the most conspicuous correlated factor. The milk of mothers from Beijing had higher levels of the n-6 series of long-chain polyunsaturated fatty acids (LCPUFA) (C20:2, C20:3n-6, C20:4n-6, n-6PUFA/n-3PUFA, LA/ALA, and ARA/DHA) than that of Danyang, while the opposite was observed in the n-3 series of LCPUFA (C18:3n-3 and Total n-3PUFA). Compared to the milk of mothers with a high school degree or below, those with a bachelor's degree or above had lower SFAs (C10:0, C12:0, C14:0, and Total SFA), n-3 series of LCPUFA (C18:3n-3 and Total n-3PUFA), C18:1n-9t, and higher n-6 series of LCPUFA (C18:2n-6c, C20:2, C20:4n-6, Total n-6PUFA, and n-6PUFA/n-3PUFA). Maternal age, infant gender, pre-conception body mass index (BMI), parity, delivery mode, and gestational weight gain were also associated with total FAs. However, fewer associations were found between the above factors and sn-2 FAs. This study will promote an understanding of human breast milk's lipid profile and help develop a formula more suitable for infants.

What Are the Maternal Factors that Potentially Intervenes in the Nutritional Composition of Human Milk?

Background: To evaluate the potential factors associated with the nutritional composition of human milk of puerperal women. Methods: cross-sectional study, conducted between March 2016 and August 2017, with 107 women, selected in a Tertiary Health Care Tertiary Health Facility of the Unified Health System (SUS) in the Municipality of Rio de Janeiro. Data were collected two months after delivery. The dependent variable of the study was the nutritional composition of human milk. We divided the independent variables into hierarchical levels: distal (age, schooling, parity and pregestational nutritional status), intermediate (number of prenatal visits and gestational weight gain) and proximal (alcohol consumption, smoking, diabetes mellitus and hypertension). For data analysis, we applied the multiple linear regression, centered on the hierarchical model. Only the variables associated with the nutritional composition of breast milk remained in the final model at a 5% level of significance. Results: The nutritional composition of human milk yielded by women with pregestational overweight, smokers and hypertensive had higher amounts of lipids and energy. Conversely, women with gestational weight gain below the recommended had lower amounts of these components. Conclusion: The evaluation of factors associated with the nutritional composition of human milk is extremely important to assist post-partum care practices. In this study, we observed that lipid and energy contents were associated to pregestational nutritional status, gestational weight gain, smoking and hypertension.

Impact of pre-pregnancy excessive body weight on the composition of polyunsaturated fatty acids in breast milk: a systematic review

This study aims to identify through a systematic review the possible effects of pre-gestational excessive body weight on the composition of polyunsaturated fatty acids in human milk. The papers were selected in the following databases: PubMed, Virtual Health Library, EMBASE, Web of Science and SCOPUS. The search strategy employed descriptors: 'Human Milk' AND 'Obesity' OR 'Overweight' OR 'Body Mass Index' AND 'Fatty acid' OR 'Omega3' OR 'Omega6'. According to the established strategy, six manuscripts were selected. Most of the selected studies concluded that mothers with excessive body weight presented a milk with a higher concentration of omega 6. In addition, all selected studies identified an increased Omega-6/Omega-3 ratio in the milk of pre-gestational excessive body weight mothers compared to the eutrophic ones. The milk of pre-gestational excessive body weight women had a higher Omega-6/Omega-3 ratio, which confirms the importance of starting pregnancy with adequate weight, thus minimising the possible influences that excessive body weight can cause infant health.

Overweight modifies the nutritional composition of human milk? A systematic review

This paper aims to identify the association between overweight and the nutritional composition of human milk. A systematic review was performed by searching on PubMed, Virtual Health Library (BVS), EMBASE, Web of Science, and SCOPUS databases, from May to June 2018, using keywords "Human Milk" AND "Overweight" OR "Obesity" OR "Body Mass Index". The bibliographic search returned 435 papers after the duplicates were removed. Of this total, 12 papers were selected for abstract reading, and nine works were incorporated into this systematic review. Eight papers showed that overweight increased the total concentration of lipids or glucose or macronutrient fractions, and only one study found no association between overweight and the nutritional composition of human milk. Most works selected evidenced that obesity changed the total concentration of lipids and their fractions. Thus, we recommend that women's weight and height be evaluated in the pregestational visit to identify and monitor nutritional deviations, contributing to weight adequacy before pregnancy and assisting in the production of milk with adequate nutritional composition.

Lipid profile of different infant formulas for infants

Situations including premature infants, or those in which there is a rejection to breastfeeding, require the use infant formulas for total or partial replacement of human milk. The objective of this study was to determine the lipid content and to identify the lipid profile of infant formulas. Samples were collected from ten different infant formulas, used as a substitute for breast milk at the Maternal and Child Hospital of Brasilia. The human milk sample consisted of a pool of samples from 10 mature milk donors at the milk bank of the University Hospital of Brasilia. The lipid content and lipid profile of the different infant formulas and human milk were analyzed. The experiment was conducted in a randomized block design, with eleven treatments and three replicates, in triplicate. The data obtained in this study indicated significant differences between infant formulas and human milk, and among the infant formulas analyzed in relation to the percentage of total lipids and the fatty acid profile, except for the fractions of linoleic acid and linolenic acid. Regarding the percentage of polyunsaturated fatty acids in relation to the total unsaturated fatty acids, only the Soy Protein Isolate-based Infant Formula (SPIIF) and Whey Protein Extensively Hydrolyzed Infant Formula (WPEHIF) resembled human milk. It was concluded that despite the observed differences, the use of infant formulas is a viable strategy for the development of infants subjected or not to specific physiological conditions.

Supplementation with the omega-3 docosahexaenoic acid: influence on the lipid composition and fatty acid profile of human milk

OBJECTIVE: This study assessed the impact of supplementing the diet of women during pregnancy and lactation with fish oil containing the omega-3 fatty acid docosahexaenoic acid, and its influence on the composition of human milk. METHODS: The sample comprised 60 women aged 18 to 38 years with appropriate dietary pattern, all of them healthy and nonsmokers. The intervention consisted of a daily supplementation with fish oil capsules that corresponded to a daily intake of 315mg of docosahexaenoic acid and 80mg of eicosapentaenoic acid during the third trimester of pregnancy and the first three months postpartum. The total fat content and fatty acid profile of their milk were determined by creamatocrit and gas chromatography. Descriptive statistics were used for data analysis and the significance level was set at p<0.05. RESULTS: There was no statistical difference between the fat contents of the study (fish oil capsules) and control (capsules containing corn starch as filler) groups. However, the milk of women taking fish oil contained higher docosahexaenoic and eicosapentaenoic acid levels 30 and 60 days after delivery. These results demonstrate that high omega-3 intake can influence its concentration in human milk. CONCLUSIONS: Given the importance of docosahexaenoic acid in the neonatal period, it is appropriate for pregnant and breastfeeding women to supplement on long-chain polyunsaturated fatty acids, which may be done by adding fish oil to the regular diet.