B-Vitamin Levels in Human Milk among Different Lactation Stages and Areas in China

Longitudinal Changes in Human Milk Minerals and Vitamins in the Chinese Population: A Scoping Review

This scoping review aims to investigate longitudinal changes in minerals and vitamins concentrations in human milk among the Chinese population. Following the PRISMA-ScR guidelines, a comprehensive and systematic literature search was conducted using both English and Chinese databases. Data were extracted and categorized into six defined lactation stages. We found that the concentration of most minerals decreased throughout the lactation period, although calcium (Ca) and magnesium (Mg) fluctuated slightly across lactation periods. Fat-soluble vitamins also showed a decline throughout the lactation period, while water-soluble vitamins exhibited an increasing trend. However, folic acid, biotin, and pantothenic acid demonstrated a downward trend. Overall, this review has identified the longitudinal changes in minerals and vitamins concentrations in human milk among the Chinese population. In order to conduct a more in-depth examination of maternal characteristics and nutritional factors of the composition of human milk, it is recommended to utilize standardized protocols for the collection and analysis of human milk samples.

A nutritional supplement during preconception and pregnancy increases human milk vitamin D but not B-vitamin concentrations

BACKGROUND & AIMS

Optimal maternal vitamin status during pregnancy and lactation is essential to support maternal and infant health. For instance, vitamin D3 is involved in infant bone development, and B-vitamins are involved in various metabolic processes, including energy production. Through a double-blind randomised controlled trial, we investigated the effects of maternal supplementation from preconception throughout pregnancy until birth on human milk (HM) concentrations of vitamin D3 and B-vitamins. In addition, we aimed to characterise longitudinal changes in milk concentrations of these vitamins.

METHODS

Both control and intervention supplements contained calcium, iodine, iron, β-carotene, and folic acid, while the intervention also contained zinc, vitamins B2, B6, B12, and D3, probiotics, and myo-inositol. HM samples were collected across 4 time points from 1 week to 3 months post-delivery from 158 mothers in Singapore, and 7 time points from 1 week to 12 months from 180 mothers in New Zealand. HM vitamin D was quantified using supercritical fluid chromatography and B-vitamins with mass spectrometry. Potential intervention effects on HM vitamins D3, B2, B6, and B9, as well as other B-vitamin (B1 and B3) concentrations were assessed using linear mixed models with a repeated measures design.

RESULTS

Over the first 3 months of lactation, HM 25-hydroxyvitamin D3 concentrations were 20% (95% CI 8%, 33%, P = 0.001) higher in the intervention group, with more marked effects in New Zealand. There were no observed intervention effects on HM concentrations of vitamins B1, B2, B3, B6, and B9. In New Zealand mothers, longitudinally, vitamin D3 concentrations gradually increased from early lactation up to 12 months, while vitamins B1 and B2 peaked at 6 weeks, B3 at 3 weeks, and B6 and B9 at 3 months.

CONCLUSIONS

Maternal supplementation during preconception and pregnancy increased HM vitamin D, but not B-vitamin concentrations in lactation. Further studies are required to examine the discrete benefits of vitamin D supplementation starting preconception vs during pregnancy, and to further characterise the effects of supplementation on later offspring health outcomes.

CLINICAL TRIAL REGISTRATION

Registered at ClinicalTrials.gov on the 16 July 2015 (identifier NCT02509988); Universal Trial Number U1111-1171-8056. This study was academic-led by the EpiGen Global Research Consortium.

Milk Properties and Morphological Characteristics of the Donkey Mammary Gland for Development of an Adopted Milking Machine—A Review

Donkey milk (DM) has been known in the world for 5000 years for its benefits for human nutrition and health. Nowadays, DM has become more and more attractive as a commercial product. DM contains several physiologically functional components, including high-quality whey proteins, vitamins, important minerals, unsaturated fatty acid and bioactive components. Therefore, it is not only consumed as food but also as a remedy. The average daily milk yield of a female donkey over the entire lactation season was 1.57 ± 1.12 kg/day and fluctuated between 0.20 and 6.00 kg/day. Average milk concentrations (±SD) of fat, protein, lactose, total solids and ash in DM were 0.63 ± 0.41%, 1.71 ± 0.24%, 6.34 ± 0.37%, 9.11 ± 0.95% and 0.39 ± 0.04%, respectively. Interestingly, DM is similar in composition to mare’s milk, and both are similar to mother’s milk. The anatomical and morphological properties of the mammary gland of the female donkey are special and can be compared with those of mare udders. However, the cistern cavity of the mammary gland of female donkeys is characterized by the presence of multiple pockets that open directly into the teat, instead of a single cistern cavity. Therefore, the mammary gland capacity in donkey mare is low and milking technique and routine are of most importance. So far there is no special milking machine for female donkeys and mares. The milking machines used nowadays were initially designed for smaller sheep and goat udders. The company Siliconform, Germany, has set itself the task of developing an optimized milking machine for donkey mares, which is adapted to the anatomical and morphological properties of the donkey mammary gland. Furthermore, it should achieve a physiologically ideal milking process meeting high animal welfare standards for increased milk production with high quality standards.

B-Vitamins and Choline in Human Milk Are Not Impacted by a Preconception Lipid-Based Nutrient Supplement, but Differ Among Three Low-to-Middle Income Settings-Findings From the Women First Trial

Introduction: Optimal human milk (HM) B-vitamin concentrations remain undefined, especially in areas where undernutrition is prevalent. The impact of supplementation pre-conception through pregnancy on HM B-vitamin composition remains unknown.

Methods: Human milk (HM) was collected at 2-weeks postpartum from 200 women in Guatemala, India, and Pakistan (the Women First Trial). The women were randomized to start a lipid-based nutrient supplement before conception, at end of the first trimester, or not at all; intervention continued until delivery. HM concentrations of eight B-vitamins and choline were assessed via ultra-performance liquid chromatography-tandem mass spectrometry. Maternal diet was assessed in early pregnancy, and infant growth followed through 6 months post-delivery.

Results: Despite supplement exposure averaging 15.7 (pre-conception arm) and 6.0 months (prenatal arm), HM B-vitamins did not differ between arms, but site differences were evident. Guatemala had higher HM concentrations of vitamin B3 than Pakistan and India. Pakistan had higher HM concentrations of thiamin and vitamin B6 than India and Guatemala. Cohort average HM vitamin B2 (162 ± 79 μg/L) and B6 (31.8 ± 24.6 μg/L) fell below values defined as deficient in 81.5 and 85.5% of samples, potentially reflecting sampling procedures and timing. Maternal dietary intakes of only vitamin B6 and choline were associated with the corresponding concentrations in HM (p < 0.005). No HM B-vitamin concentrations were associated with infant growth.

Conclusion: Prenatal supplementation for at least 6 months had no impact on HM B-vitamin concentrations at 2-weeks postpartum. Results suggest that the adequacy of HM composition was generally maintained, with potential exceptions of vitamin B2 and B6.

Vitamins in Human and Donkey Milk: Functional and Nutritional Role

BACKGROUND

Whole milk is a good source of all the nutrients, and it also contains a sufficient number of vitamins to permit regular the growth of the neonate. Dairy cow milk can create allergy in infants less than 12 months old because of the high caseins and β-lactoglobulin content. In these circumstances, donkey milk can represent a good replacement for dairy cows' milk in children affected by Cow Milk Protein Allergy (CMPA) because of its close chemical composition with human milk, mainly due to its low protein and low mineral content. Milk vitamin content is highly variable among mammalian species and it is strictly correlated with the vitamin status and the diet administered to the mother. Fat-soluble vitamins content in donkey milk is, on average, lower compared to ruminants' milk, while vitamin C content determined in donkey milk is higher compared to dairy cows' milk, showing a great similarity with human milk. In donkey milk, the content of vitamins of the B-complex such as thiamine, riboflavin, niacin, pyridoxine, and folic acid is higher compared to human milk. The use of donkey milk as a new functional food must be further evaluated in interdisciplinary clinical trials in which pediatricians, dietitians, and food scientists must be involved to deepen the knowledge about the positive health impact of donkey milk in different sensitive people, especially children and the elderly.

B-Vitamins Determination in Donkey Milk

Background: Donkey milk is used in infant nutrition for the treatment of children affected by cow’s milk protein allergy, thanks to its hypo-allergenicity, mainly due to its protein profile, which is very close to that of human milk. Furthermore, donkey milk is characterized by the presence of a fair amount of bioactive proteins, that may have a positive impact on human health. Despite the presence of numerous articles that describe the chemical composition and nutraceutical properties of donkey milk, few works have been performed to determine its vitamin profile; therefore, the purpose of this work is to give further information on the B-vitamins profile of donkey milk. Methods: B-vitamins have been determined through a reversed-phase liquid chromatography analysis. Results: The results indicated that donkey milk (DM) contains thiamine 0.661 ± 0.26 μM, riboflavin 0.168 ± 0.04 μM, nicotinic acid 18.75 ± 1.92 μM, pyridoxine 5.38 ± 3.3 5μM, and folic acid 0.83 ± 0.08 μM. Conclusions: Donkey milk contains a high quantity of nicotinic acid, known for its lipid-lowering effect, and a good amount of vitamin B6 and folic acid, the latter very important for children’s growth. To notice, vitamin B6 has been determined for the first time in donkey milk.

Dietary intake in lactating mothers in China 2018: report of a survey

Background

The nutritional status of lactating mothers (LMs) is related to their own health and significantly impacts the secretion of breast-milk, and subsequently the growth and development of infants. Due to the influence of regional economy, traditional habits, and lack of nutrition knowledge, the problem of poor dietary nutrition among Chinese LMs is prominent. We aimed to evaluate and compare the dietary and nutrient intakes in LMs from urban and rural areas in China to provide baseline data for the implementation of relevant health guidance and strategies.

Methods

A multi-stage sampling method was used to recruit urban and rural LMs from 13 provinces and municipalities in China. An online dietary record using food photographs was employed to keep track of what the LMs had eaten in 2 days in the form of face-to-face interview. A total of 954 participants were included in the final analysis. Data expressed as quartiles P50 (P25; P75) were compared using the Mann-Whitney U-test (level of significance: p < 0.05).

Results

The consumption of staple food was higher in the rural (283.37 g/d) than in the urban areas (263.21 g/d). The consumption of vegetables, fruits, fish, shrimp, and shellfish, milk and dairy products was lower than the recommended amounts in both areas, and the insufficient intake of these food types was more serious in rural areas. While the energy intake of 83.8% of all LMs was lower than the estimated energy reference, it was comparable in the urban and rural areas. The intake of macronutrients (carbohydrates, protein, and fats) in rural areas was lower than in urban areas. The intake of some vitamins (VA, VB₁, VB₂, VB₉ and VC) and minerals (calcium, magnesium, iodine and copper) was not ideal for LMs in both rural and urban areas.

Conclusions

Overall, the dietary intake in LMs was lower than the recommended levels. Many essential nutrients failed to meet the recommended doses, both in the urban and rural areas. The deficiencies in micronutrients were more prevalent in rural compared to urban areas. Educating LMs about women’s health and appropriate dietary intake is, therefore, essential.

A Comparison of Vitamin and Lutein Concentrations in Breast Milk from Four Asian Countries

Vitamins are the essential elements for human life and, particularly, for infant health. Human milk is the best source of nutrients for newborns, however, the information of vitamins in Asian maternal milk is still limited. In this study, we have collected 580 Asian maternal milk samples from Korea (n = 254), China (n = 137), Pakistan (n = 92), and Vietnam (n = 97). The vitamin concentrations, including vitamin B-groups (8 vitamins), fat-soluble vitamin (retinol, D, E, K) and lutein in the breast milk of were investigated. The concentration of thiamin (B1), biotin (B7), and folic acid (B9) in mother's milk of four countries were not considerably different, while riboflavin (B2), pantothenic acid (B5), and pyridoxine (B6) level in Vietnam samples were significantly lower than those in other countries. In contrast, retinol (A) and tocopherol (E) were found to be higher levels in Vietnamese maternal milk. Korean and Chinese maternal milk had low concentrations of retinol that may cause vitamin A deficiency in children. However, Chinese mother's milk was distinguished with a high concentration of lutein. Pakistani mother's milk was observed as having a significant problem of folic acid (B9) deficiency. Regardless of the country, vitamin B12, K, and D did not seem to be provided sufficiently through maternal milk. The moderate positive correlations were found between vitamin concentrations in each country and the pooled sample. The data obtained in this study were able to provide vital information to assess the nutritional status of breast milk in Asian countries and contributed to the efforts of ensuring the best nutrition for Asian children.

Quantification of B-vitamins from different fresh milk samples using ultra-high performance liquid chromatography mass spectrometry/selected reaction monitoring methods

Absolute quantification of B-vitamins in milk is becoming imperative to correlate its impact on child/human health. In today's world of changing food habits and environmental pollution, there is concern if milk is what we think it to be. In the present work, ultra-high performance liquid chromatography mass spectrometry/selected reaction monitoring (UPHPLC-MS/SRM) methods have been developed and validated for quantitative estimation of 21 different B-vitamins [B1-3, B2-3, B3-2, B5-1, B6-5, B8-1, B9-2 vitamins, total choline (betaine, choline and acetylcholine)] from a drop (50 µL) and B12 from 500 µL of milk. These two methods qualify all essential bio-analytical parameters (recovery >80%, accuracy <±15%, variation <±10%) and are highly reproducible. By using these developed methods, B-vitamins in different fresh milk samples from cow, goat, buffalo and pasteurized cow milk (each 10 and total n = 40) were analysed. Total choline is the highest (6.5-10.5 µg/mL) and vitamin B8 is the lowest (16.1-32.9 ng/mL) in all milk samples. Inverse correlation between vitamin B2 and B5 was observed in milk samples. The ratio of vitamin B5/B2 was checked in all milk samples, it is higher in cow (2.64), equal in goat (1.04) and lower in buffalo (0.42) milk. Total B-vitamin content in cow milk is higher (10.5 µg/mL) compared to other three (goat-7.2, buffalo-6.5, pasteurized-8.8 µg/mL). Vitamin B12 is higher in cow milk (3.6 ng/mL) compared to other two fresh milk samples. Different isomers for vitamin B6 were noticed in the fresh milk samples. The complete profile of water soluble vitamins and the ratio of two abundant B vitamins (B5/B2) in milk will be useful to check the nutritional quality and to differentiate the kind of animal milk.

Changes in the metabolite profile of breast milk over lactation stages and their relationship with dietary intake in Chinese women: HPLC-QTOFMS based metabolomic analysis

The aim of the present study was to comprehensively evaluate the changes in the metabolite profile of breast milk over lactation stages and their relationship with dietary intake in Chinese women by HPLC-QTOFMS based metabolomic analysis. The colostrum, transitional milk and mature milk of thirty healthy lactating women were collected for analysis. Eighty-four differential metabolites over lactation stages were identified, including 12 fatty acyls, 15 glycerolipids, 23 glycerophospholipids, 7 sphingolipids, 7 vitamins, 5 nucleotides-related metabolites, 2 amino acids, 1 amino acid derivate, 9 dipeptides, 1 steroid hormone, 1 energy-related metabolite and 1 amine. Partial least-squares regression analysis indicated that the metabolite profiles of the colostrum, transitional milk and mature milk have a strong relationship with dietary intake (R2 values were 0.92, 0.87 and 0.74, respectively). However, among the 84 differential metabolites over lactation stages, only two showed a strong relationship with dietary intake: 1,24,25-(OH)3 vitamin D3 was positively correlated with the dietary intake of meat and eggs, protein and fat; 11β-hydroxyprogesterone was negatively correlated with the dietary intake of fruit and carbohydrate. After adjusting for dietary intake, the variation trend of all the 84 differential metabolites over lactation stages remained unchanged. In conclusion, 84 differential metabolites in the breast milk of Chinese women over lactation stages were identified, and their variation trend was independent of dietary intake. These metabolites were partially different from those identified in previous metabolomic studies in the Western population. The present study is quite meaningful for understanding the variation of nutritional requirements in Chinese infants at different developmental stages and manufacturing optimal infant formulas for them.

Geography and ethnicity related variation in the Chinese human milk serum proteome

Human milk provides a range of nutrients and bioactive components, which can support the growth and development of infants.

Micronutrients in Human Milk: Analytical Methods

Exclusive breastfeeding is recommended by the WHO for the first 6 mo of life because human milk protects against gastrointestinal infections and supplies balanced and adequate nutrient contents to the infant. However, reliable data on micronutrient concentrations in human milk are sparse, especially because some micronutrients are affected by maternal diet. Microbiological and competitive protein-binding assays, nuclear magnetic resonance or inductively coupled plasma spectroscopy, and chromatographic analyses are among the methods that have been applied to human-milk micronutrient analysis. However, the validation or evaluation of analytical methods in terms of their suitability for the complex human-milk matrix has been commonly ignored in reports, even though the human-milk matrix differs vastly from blood, plasma, or urine matrixes. Thus, information on the validity, accuracy, and sensitivity of the methods is essential for the estimation of infant and maternal intake requirements to support and maintain adequate milk micronutrient concentrations for healthy infant growth and development. In this review, we summarize current knowledge on methods used for analyzing water- and fat-soluble vitamins as well as iron, copper, zinc, iodine, and selenium in human milk and their different forms in milk; the tools available for quality control and assurance; and guidance for preanalytical considerations. Finally, we recommend preferred methodologic approaches for analysis of specific milk micronutrients.

Vitamin Concentrations in Human Milk Vary with Time within Feed, Circadian Rhythm, and Single-Dose Supplementation

Background: Human milk is the subject of many studies, but procedures for representative sample collection have not been established. Our improved methods for milk micronutrient analysis now enable systematic study of factors that affect its concentrations.Objective: We evaluated the effects of sample collection protocols, variations in circadian rhythms, subject variability, and acute maternal micronutrient supplementation on milk vitamin concentrations.Methods: In the BMQ (Breast-Milk-Quality) study, we recruited 18 healthy women (aged 18-26 y) in Dhaka, Bangladesh, at 2-4 mo of lactation for a 3-d supplementation study. On day 1, no supplements were given; on days 2 and 3, participants consumed ∼1 time and 2 times, respectively, the US-Canadian Recommended Dietary Allowances for vitamins at breakfast (0800-0859). Milk was collected during every feeding from the same breast over 24 h. Milk expressed in the first 2 min (aliquot I) was collected separately from the remainder (aliquot II); a third aliquot (aliquot III) was saved by combining aliquots I and II. Thiamin, riboflavin, niacin, and vitamins B-6, B-12, A, and E and fat were measured in each sample.Results: Significant but small differences (14-18%) between aliquots were found for all vitamins except for vitamins B-6 and B-12. Circadian variance was significant except for fat-adjusted vitamins A and E, with a higher contribution to total variance with supplementation. Between-subject variability accounted for most of the total variance. Afternoon and evening samples best reflected daily vitamin concentrations for all study days. Acute supplementation effects were found for thiamin, riboflavin, and vitamins B-6 and A at 2-4 h postdosing, with 0.1-6.17% passing into milk. Supplementation was reflected in fasting, 24-h postdose samples for riboflavin and vitamin B-6. Maximum amounts of dose-responding vitamins in 1 feeding ranged from 4.7% to 21.8% (day 2) and 8.2% to 35.0% (day 3) of Adequate Intake.Conclusions: In the milk of Bangladeshi mothers, differences in vitamin concentrations between aliquots within feedings and by circadian variance were significant but small. Afternoon and evening collection provided the most-representative samples. Supplementation acutely affects some breast-milk micronutrient concentrations. This trial was registered at clinicaltrials.gov as NCT02756026.

Regional, socioeconomic, and dietary factors influencing B-vitamins in human milk of urban Chinese lactating women at different lactation stages

Background

Adequate B-vitamins concentrations in human milk are considered to be a prerequisite for healthy development of infants in early life. This study aims to determine the concentrations of B-vitamins in human milk from Chinese women and the relationships between their concentrations and different geographical origin, lactation stages, socioeconomic characteristics, and dietary intake.

Methods

Human milk was obtained from 443 healthy lactating women from Beijing (n = 150), Suzhou (n = 146), and Guangzhou (n = 147) cities. Thiamine, riboflavin, vitamin B₃ (nicotinamide and nicotinic acid), and vitamin B₆ (pyridoxal, pyridoxine, and pyridoxamine) in human milk were analyzed by high performance liquid chromatography-tandem mass spectrometry. Pantothenic acid, biotin, and folates in human milk were analyzed by microbiological assay. The information from one 24-h dietary recall and socioeconomic characteristics were collected by interview and structured questionnaire, respectively.

Results

B-vitamins concentrations in human milk varied greatly among individuals. The median concentrations of B-vitamins of postpartum 5–11 d, 12–30 d, 31–60 d, 61–120 d, and 121–240 d were respectively as follows: thiamine 3.13, 5.07, 4.28, 5.65, 6.28 (μg/100 g); riboflavin 20.8, 20.2, 11.9, 13.6, 15.6 (μg/100 g); vitamin B₃ 194.0, 300.0, 261.0, 212.5, 218.0 (μg/100 g); pantothenic acid 236.5, 291.0, 254.0, 179.0, 189.0 (μg/100 g); vitamin B₆ 6.34, 7.58, 8.60, 9.34, 10.20 (μg/100 g); biotin 0.462, 0.834, 0.606, 0.523, 0.464 (μg/100 g); folates 0.730, 2.390, 2.440, 2.420, 2.330 (μg/100 g). The levels of B-vitamins presented regional differences and varied significantly among different lactation stages. The inversely associations of thiamine, vitamin B₆, and folates with maternal BMI were found in multivariate analyses (p < 0.05), as well as higher pantothenic acid, folates, and biotin concentrations in lactating women with supplement intake when compared with those without (p < 0.05). Riboflavin concentrations associated with regular exercise was found in multivariate analyses (p < 0.05).

Conclusions

The present study indicated regional and socioeconomic factors, lactation stage, and supplement intake may influence B-vitamins concentrations of human milk in healthy Chinese mothers. Further studies on accurate and complete analysis of all vitamin forms are crucial for giving a more comprehensive understanding of vitamin status in human milk.

Trial registration

ClinicalTrials.gov, NCT01971671. Registered 13 October 2013.

Electronic supplementary material

The online version of this article (doi:10.1186/s40795-017-0139-1) contains supplementary material, which is available to authorized users.

Characteristic chromatographic fingerprint study of short-chain fatty acids in human milk, infant formula, pure milk and fermented milk by gas chromatography-mass spectrometry

Human milk, infant formula, pure milk and fermented milk as food products or dietary supplements provide a range of nutrients required to both infants and adults. Recently, a growing body of evidence has revealed the beneficial roles of short-chain fatty acids (SCFAs), a subset of fatty acids produced from the fermentation of dietary fibers by gut microbiota. The objective of this study was to establish a chromatographic fingerprint technique to investigate SCFAs in human milk and dairy products by gas chromatography coupled with mass spectrometry. The multivariate method for principal component analysis assessed differences between milk types. Human milk, infant formula, pure milk and fermented milk were grouped independently, mainly because of differences in formic acid, acetic acid, propionic acid and hexanoic acid levels. This method will be important for the assessment of SCFAs in human milk and various dairy products.