Nutritive and Bioactive Proteins in Breastmilk.

Protein ingested with breast milk provides indispensable amino acids which are necessary for new protein synthesis for growth and replacement of losses via urine, feces, and the skin. Protein gain in the body of an infant is highest during the first months when protein concentrations in breast milk are higher than during later stages of lactation. Low-birth-weight infants have higher protein needs than term infants and need protein supplements during feeding with breastmilk. Based on our better understanding of protein evolution in breastmilk during the stages of lactation, new infant formulas with lower protein concentration but better protein quality have been created, successfully tested, and are now available in many countries. Besides providing indispensable amino acids, bioactive protein in breast milk can be broadly classified into 4 major functions, that is, providing protection from microbial insults and immune protection, aiding in digestive functions, gut development, and being carriers for other nutrients. Individual proteins and their proposed bioactivities are summarized in this paper in brief. Indeed, some proteins like lactoferrin and sIgA have been extensively studied for their biological functions, whereas others may require more data in support to further validate their proposed functions.

Adequacy of Infant Formula With Protein Content of 1.6 g/100 kcal for Infants Between 3 and 12 Months.

OBJECTIVES: Infant formulas provide more protein than breast milk. High protein intakes may place infants at risk of later obesity. The present study tested whether a formula with protein content below the regulatory level supports normal growth from age 3 months. METHODS: Randomized double-blind trial enrolled healthy infants less than age 3 months. At 3 months, formula-fed infants were assigned to experimental (EXPL, 1.61 g protein/100 kcal; modified bovine whey proteins with caseinoglycomacropeptide removed) or control (CTRL 2.15 g protein/100 kcal; unmodified bovine milk protein with a whey/casein ratio of 60/40) formula; breast-fed (BF) infants were enrolled in a reference group. Complementary foods were allowed in small amounts from 4 to 6 months and unrestricted after 6 months. RESULTS: Weight gain (g/day) from 3 to 6 months was similar in the EXPL and CTRL groups (EXPL-CTRL -0.84 g/day; 95% confidence interval -2.25 to 0.57) and faster in the EXPL and CTRL groups than in the BF group. Weight analyzed longitudinally from 4 to 12 months was lower in the EXPL group than in the CTRL group (P = 0.031) but higher than in the BF group (P < 0.0001). Longitudinal analysis of odds ratios from 4 to 12 months indicated fewer infants with weight >85th percentile in the EXPL group than in the CTRL group (P = 0.015). Length z scores were lower than, and body mass index z scores were similar to, World Health Organization Standards in all of the groups. Serum biochemical parameters in the EXPL group reflected lower protein intake and were closer to parameters in the BF infants than in the CTRL group. CONCLUSIONS: A formula with 1.61 g of protein/100 kcal supports normal growth of infants after age 3 months. This protein content is adequate if provided from a high-quality source.

Low-protein formula slows weight gain in infants of overweight mothers.

OBJECTIVES: Infant formulas provide more protein than breast milk. High protein intakes, as well as maternal obesity, are risk factors for later obesity. The present study tested whether a formula with lower protein content slows weight gain of infants of overweight mothers (body mass index [BMI] >25 kg/m). METHODS: In a randomized double-blind study infants of overweight mothers received from 3 months an experimental (EXPL) formula with 1.65 g of protein/100 kcal (62.8 kcal/100 mL) and containing probiotics, or a control (CTRL) formula with 2.7 g of protein/100 kcal (65.6 kcal/100 mL). Breast-fed infants were studied concurrently. Primary assessment was between 3 and 6 months, although formulas were fed until 12 months. Biomarkers of protein metabolism (blood urea nitrogen, insulin growth factor-1, insulinogenic amino acids) were measured. RESULTS: Infants fed the low-protein EXPL formula gained less weight between 3 and 6 months (-1.77 g/day, P=0.024) than infants fed the CTRL formula. In the subgroup of infants of mothers with BMI>30 kg/m the difference was -4.21 g/day (P=0.017). Weight (P=0.011) and BMI (P=0.027) of EXPL infants remained lower than that of CTRL infants until 2 years but were similar to that of breast-fed infants. Blood urea nitrogen, insulin growth factor-1, and insulinogenic amino acids at 6 months were significantly lower in EXPL compared with CTRL. CONCLUSIONS: A low-protein formula with probiotics slowed weight gain between 3 and 6 months in infants of overweight mothers. Weight gain and biomarkers were more like those of breast-fed infants.

Fast growth of infants of overweight mothers: can it be slowed down?

Data from 3 recently completed studies were pooled and analyzed to answer the question whether breastfed infants of overweight/obese mothers show accelerated growth. It was shown that these infants gain weight faster than indicated by the WHO standards and that they grow significantly faster than infants of lean mothers. The question whether fast infant growth can be slowed down by lowering the protein content of formulas was examined. It was shown that formulas with a protein content that is just moderately above that of human milk support normal growth while significantly slowing down fast growth.

Feeding patterns during the first 2 years and health outcome.

Low-birth-weight infants, in particular those with birth weights <1,500 g, benefit from fortified breast milk. Low protein intake is critical, because it is limiting growth. Long-term health outcomes in small-for-gestational-age infants from developing countries in relation to their early nutrition still need to be evaluated in controlled trials. Term infants both in developing and developed countries also benefit from exclusive breastfeeding: an analysis of a large dataset of surveys from 20 developing countries (168,000 infants and small children from the Demographic Health Survey, United States Agency for International Development) indicates that exclusive breastfeeding until 6 months is associated with significantly higher weight, length, and lower probability of stunting, wasting, and infections. Nine out of 10 infants still receive breast milk between 6 and 12 months and probability of infections tends to be lower if breastfeeding is continued during that age range. Between 12 and 24 months, when stunting and wasting rates are already high, 7 out of 10 infants still receive breast milk. No associations of feeding patterns with disease outcome can be found. Effectiveness trials of complementary feeding strategies in food-insecure countries are urgently needed. Follow-up until 10 years in a developed country now indicates that an infant population at risk for allergic diseases benefits both from breastfeeding and the use of hypoallergenic formula during the first 4 months of life, when compared to cow's milk-based formula: both the cumulative incidences of atopic disease and all allergic diseases are significantly lower.

Early Nutrition Must Be Safe and Should Have Positive Impacts on Long-Term Health.

The Special Issue entitled 'The Role of Feeding Practice and Early Nutrition in Infant Growth, Metabolism and Body Composition' examines the long-term outcomes of early nutrition in both preterm and term infants [...].

Effects of Movement Behaviors on Overall Health and Appetite Control: Current Evidence and Perspectives in Children and Adolescents.

PURPOSE OF REVIEW: To present the definitions and recommendations for movement behaviors in children and adolescents, including physical activity (PA), sedentary behaviors (SB), and sleep, and to provide an overview regarding their impact on health and obesity outcomes from childhood to adulthood, as well as interactions with appetite control. RECENT FINDINGS: PA represents a variable proportion of daily energy expenditure and one can be active with high SB or vice versa. Studies have described movements across the whole day on a continuum from sleep to SB to varying intensities of PA. More PA, less SB (e.g., less screen time) and longer sleep are positively associated with indicators of physical health (e.g., lower BMI, adiposity, cardiometabolic risk) and cognitive development (e.g., motor skills, academic achievement). However, less than 10% of children currently meet recommendations for all three movement behaviors. Movement behaviors, adiposity, and related cardiometabolic diseases in childhood track into adolescence and adulthood. Furthermore, low PA/high SB profiles are associated with increased energy intake. Recent studies investigating energy balance regulation showed that desirable movement behavior profiles are associated with better appetite control and improved eating habits. Early identification of behavioral phenotypes and a comprehensive approach addressing all key behaviors that directly affect energy balance will allow for individual strategies to prevent or treat obesity and its comorbidities. Investigating exercise as a potential "corrector" of impaired appetite control offers a promising weight management approach.

External validation of a prediction model for estimating fat mass in children and adolescents in 19 countries: individual participant data meta-analysis.

OBJECTIVE: To evaluate the performance of a UK based prediction model for estimating fat-free mass (and indirectly fat mass) in children and adolescents in non-UK settings. DESIGN: Individual participant data meta-analysis. SETTING: 19 countries. PARTICIPANTS: 5693 children and adolescents (49.7% boys) aged 4 to 15 years with complete data on the predictors included in the UK based model (weight, height, age, sex, and ethnicity) and on the independently assessed outcome measure (fat-free mass determined by deuterium dilution assessment). MAIN OUTCOME MEASURES: The outcome of the UK based prediction model was natural log transformed fat-free mass (lnFFM). Predictive performance statistics of R2, calibration slope, calibration-in-the-large, and root mean square error were assessed in each of the 19 countries and then pooled through random effects meta-analysis. Calibration plots were also derived for each country, including flexible calibration curves. RESULTS: The model showed good predictive ability in non-UK populations of children and adolescents, providing R2 values of >75% in all countries and >90% in 11 of the 19 countries, and with good calibration (ie, agreement) of observed and predicted values. Root mean square error values (on fat-free mass scale) were <4 kg in 17 of the 19 settings. Pooled values (95% confidence intervals) of R2, calibration slope, and calibration-in-the-large were 88.7% (85.9% to 91.4%), 0.98 (0.97 to 1.00), and 0.01 (-0.02 to 0.04), respectively. Heterogeneity was evident in the R2 and calibration-in-the-large values across settings, but not in the calibration slope. Model performance did not vary markedly between boys and girls, age, ethnicity, and national income groups. To further improve the accuracy of the predictions, the model equation was recalibrated for the intercept in each setting so that country specific equations are available for future use. CONCLUSION: The UK based prediction model, which is based on readily available measures, provides predictions of childhood fat-free mass, and hence fat mass, in a range of non-UK settings that explain a large proportion of the variability in observed fat-free mass, and exhibit good calibration performance, especially after recalibration of the intercept for each population. The model demonstrates good generalisability in both low-middle income and high income populations of healthy children and adolescents aged 4-15 years.

Partially hydrolysed 100% whey-based infant formula and the prevention of atopic dermatitis: comparative pharmacoeconomic analyses.

Clinical trials have demonstrated that the risk of developing atopic dermatitis is reduced when using hydrolysed formulas to feed infants with a documented risk of atopy (i.e. an affected parent and/or sibling)when breastfeeding is not practised. However, little is known about the cost-effectiveness of using hydrolysed formulas. Consequently, economic analyses in 5 European countries (Denmark, France, Germany, Spain and Switzerland) have evaluated the costs and cost-effectiveness of a specific brand of 100% whey-based partially hydrolysed infant formula, NAN-HA® (PHF-W) compared with a cow's milk standard formula (SF) in the prevention of atopic dermatitis in at-risk children. This review synthesises the findings of these studies. Cost-effectiveness analyses (CEA) used a decision-analytic model to determine treatment pathways, resource utilisation and costs associated with the management of atopic dermatitis in healthy at-risk newborns who were not exclusively breastfed. The model had a 12-month horizon and applied reimbursement rates of 60-100% depending on the country. Outcomes were considered from the perspective of the public healthcare system (e.g. the Ministry of Health; MOH), family and society. The final outcome was the incremental cost-effectiveness ratio per avoided case of atopic dermatitis (ICER) for PHF-W versus SF. A cost-minimisation analysis was also performed to compare PHF-W with extensively hydrolysed formulas (EHF). The base-case CEA produced ICERs per avoided case for PHF-W versus SF of EUR 982-1,343 (MOH perspective), EUR -2,202 to -624 (family perspective) indicating savings, and EUR -1,220 to 719 from the societal perspective. The main costs related to formula (MOH and society) and time loss (family). In the cost-minimisation analysis, PHF-W yielded savings of between EUR 4.3 and 120 million compared with EHF-whey when the latter was used in prevention. In conclusion, PHF-W was cost-effective versus SF in the prevention of atopic dermatitis and cost saving compared with EHF when used in prevention.

New Ways to Provide a Human Milk Fortifier during Breastfeeding.

Providing a human milk fortifier once the preterm infant has started to suckle at the breast can be challenging for the mother and might shorten duration of the breastfeeding period. Fortification is recommended up to term for the normal-growing infant and up to 3 months in growth-retarded infants. After hospital discharge, some mothers may not want to pump, fortify, and bottle-feed the fortifier-milk mixture any longer. They desire to breastfeed their infants directly from the breast, but unfortunately, fortification often interferes with direct breastfeeding. Cup feeding is the most researched fortification method and appears to be safe but cannot be applied during nursing. Another alternative is the supplemental nursing systems, but only a few low-quality studies investigated the method, which is difficult to handle and requires a lot of nursing experience. The use of a finger feeder to administer a fortifier to preterm infants is a new method that enables mothers to exclusively breastfeed their infants and meet their nutritional needs. Mothers reported easy preparation and handling of the fortifier. More than 67% of the infants accepted the device and fortifier application during nursing very well. However, the development of further methods to augment preterm infant nutrition that does not interfere with breastfeeding is of great interest. Future efforts to enable fortification during breastfeeding must be linked to the development of ready-to-use devices containing liquid human milk fortification mixtures.

Human Milk Fortifiers for Preterm Infants: Do We Offer the Best Amino Acid Mix?

For preterm and small-for-gestational age infants on enteral nutrition, the best solution is to add human milk fortifier (HMF) to human milk (HM) which is provided by the mother or a milk bank. HMF provides a means to add additional protein, energy, and micronutrients, while maintaining HM as the main source of nutrition. Because of their rapid increase of lean body mass, preterm infants have much higher protein requirements than term infants. Recommendations on protein requirements of preterm infants are available, but protein quality - i.e. the amino acid (AA) profile in HMFs has not been systematically assessed. Present guidelines for enteral nutrition recommend protein intakes around 4 g/kg body weight (BW) for preterm infants <1,500 g, an intake that is not achievable with unfortified HM intakes <200 mL/kg BW/day. It is generally assumed that the AA profile of HM is the best reference for the AA profile of HMF. We calculated advisable intakes of AAs for preterm infants between 400-2,500 g which are based on AA increments of the fetus. Corrections for absorption, inevitable losses, oxidation, and variation of AAs in HM were introduced. Our calculations indicate that extremely low birth weight (ELBW <1,000 g) and very low birth weight (VLBW <1,500 g) infants have substantially higher AA requirements than low birth weight (LBW) infants growing from 1,900 to 2,400 g. In ELBW infants, daily intakes of the different indispensable AAs (IAA) with 4 g of (term) HM protein/kg BW range between 59 and 125% of the respective advisable intakes. Intakes of 7 IAAs and 3 conditionally indispensable AAs (CIAA) are below advisable intakes. On the other hand, with 4 g HM protein per kg BW/day, the IAAs isoleucine and leucine and some dispensable AAs are already supplied in abundance. In VLBW infants, daily intakes of the IAA methionine and 3 CIAAs are still below the advisable intakes. In LBW infants (<2,000 g) receiving 3.5 g HM protein per kg BW daily intakes of 1 IAA and 3 CIAAs would be too low. Preterm infants should receive HMFs which provide adequate amounts of AAs which are needed for their rapid growth and development while avoiding excessive intakes. In particular, very high AA requirements of ELBW infants are a challenge. AA composition of present HMFs for preterm infants should be reconsidered: spiking HMF protein with the AAs which are presently undersupplied or providing targeted AA-based HMF are options to further improve the AA profile in fortifiers.

Early-Life Nutrition, Growth Trajectories, and Long-Term Outcome.

It is well established that nutrition during the first 1,000 days of life can have a long-term effect on growth, metabolic outcome, and long-term health. We review the long-term anthropometric follow-ups of children with risk of later morbidity: (a) very-low-birth-weight (VLBW) infants who have birth weights <10th percentile of weight and receive fortified breast milk, (b) infants from developing countries who are breastfed according to the present recommendations but have low birth weight and length, and (c) children from developed countries who were enrolled in randomized controlled trials (RCTs) to test if breastfeeding and low-protein formulas can prevent from rapid weight gain and childhood obesity. VLBW infants can be appropriate, small for gestational age (SGA), or intrauterine growth retarded (IUGR). SGA and IUGR (due to placenta insufficiency) infants are born with birth weights <10th percentile of weight for gestational age (GA). We provided fortified breast milk until 52 weeks of GA to 31 SGA and 127 IUGR infants and followed up growth until 24 months. IUGR infants showed lower weight gain between birth and 3 months and had lower weight between 3 and 24 months (p < 0.05; ANCOVA). No significant BMI differences between SGA and IUGR infants were observed. It seems that IUGR infants receiving fortified breast milk need special attention, because without further improvement in breast milk fortification weight gain after discharge from hospital might be too slow. In developing countries, length and weight of breastfed infants during the first 2 years are strongly influenced by the respective anthropometric parameters at birth. Studies in the Gambia and Zimbabwe indicate that only breastfed infants with birth length and weight above the respective WHO 0 z-scores continue with adequate growth and have length and weight above the WHO 0 z-scores at 18 and 24 months. Prevalence of stunting and wasting in the overall Gambia breastfed infant population rapidly increases during the first year, peaks at around 3 years, but decreases thereafter. Long-term growth trajectories indicate later start of puberty and slow pubertal growth, but adult weight and height are not reached before 20-24 years. In adulthood, prevalence of stunting and wasting is much lower than during any period of childhood. Maternal risk factors, such as childhood marriage and poor nutrition before and during pregnancy, need to come into focus to improve birth length and weight and lower high stunting rates. Term breastfed infants from overweight/obese mothers and breastfed infants with rapid weight gain during infancy have increased risk of childhood obesity. Infants who are exclusively breastfed 4-6 months or receive low protein follow-up formulas (high-quality protein) grow slower during the first 2-3 years than infants fed high-protein formulas. During follow-up examinations at 5-6 years, they have lower BMI and obesity prevalence. Body composition measurements (DEXA) at 5-8 years in children who were breastfed and received low- or high-protein formula during infancy indicate that breastfeeding and feeding low-protein formulas are associated with lower gain of fat mass. Longitudinal cohort studies show that high-protein intake during the first 2 years results in higher BMI at 9 years and during adulthood. The studies presented indicate that breastfeeding but also other pre- and postnatal nutritional, epigenetic, and environmental factors influence growth trajectories and long-term health.

Urinary D-lactate excretion in infants receiving Lactobacillus johnsonii with formula.

BACKGROUND/AIMS: Supplementation with certain probiotics can improve gut microbial flora and immune function but should not have adverse effects. This study aimed to assess the risk of D-lactate accumulation and subsequent metabolic acidosis in infants fed on formula containing Lactobacillus johnsonii (La1). METHODS: In the framework of a double-blind, randomized controlled trial enrolling 71 infants aged 4-5 months, morning urine samples were collected before and 4 weeks after being fed formulas with or without La1 (1 x 10(8)/g powder) or being breastfed. Urinary D- and L-lactate concentrations were assayed by enzymatic, fluorimetric methods and excretion was normalized per mol creatinine. RESULTS: At baseline, no significant differences in urinary D-/L-lactate excretion among the formula-fed and breastfed groups were found. After 4 weeks, D-lactate excretion did not differ between the two formula groups, but was higher in both formula groups than in breastfed infants. In all infants receiving La1, urinary D-lactate concentrations remained within the concentration ranges of age-matched healthy infants which had been determined in an earlier study using the same analytical method. Urinary L-lactate also did not vary over time or among groups. CONCLUSIONS: Supplementation of La1 to formula did not affect urinary lactate excretion and there is no evidence of an increased risk of lactic acidosis.

Supplementation with 200 mg/day docosahexaenoic acid from mid-pregnancy through lactation improves the docosahexaenoic acid status of mothers with a habitually low fish intake and of their infants.

BACKGROUND/AIMS: The supply of docosahexaenoic acid (DHA, 22:6omega-3), important for fetal/infant neurodevelopment, depends on the maternal fatty acid (FA) status, which may be marginal in central Europe. Therefore, we investigated the effect of a daily vitamin/mineral supplement with and without 200 mg DHA from mid-pregnancy through lactation on the DHA concentrations in maternal and infant red blood cell phospholipids (RBC%), and in breast milk FA (%). METHODS: At 21 weeks' gestation, 144 women were enrolled into a randomised, double-blind clinical trial receiving daily: (1) a basic vitamin-mineral supplement (Vit/Min group), (2) Vit/Min plus 4.5 g fructo-oligosaccharide (FOS group), or (3) Vit/Min plus 4.5 g FOS plus 200 mg fish oil-derived DHA (DHA-FOS group). FAs were determined by capillary gas-liquid chromatography. RESULTS: While maternal RBC-DHA% at enrolment was not different, at 37 weeks gestation, and 3 months after delivery RBC-DHA% were significantly higher in the DHA-FOS group. The breast milk DHA% was twice as high in the DHA-FOS group (0.50%) than in the two others (0.25 %) (p < 0.001), and the ratio ARA/DHA in the DHA-FOS group was 1.0 +/- 0.43, in the others 2.1 +/- 0.43 (p < 0.001). The RBC-DHA% of the infants in the DHA-FOS group was also significantly higher, and correlated significantly with maternal RBC-DHA% before and 3 months after delivery. CONCLUSIONS: In central Europe, a dose of 200 mg/day DHA from mid-pregnancy through lactation seems appropriate to improve the DHA status of mothers and infants.