Effect of maternal consumption of lactobacillus GG on transfer and establishment of fecal bifidobacterial microbiota in neonates

The Youngest Vegetarians

As the popularity of vegetarian diets increases, practitioners are likely to encounter vegetarian infants and toddlers. Vegetarian and vegan diets can be developed to meet nutrient needs and support growth of infants and toddlers. Key nutrients whose adequacy should be monitored in vegetarian/vegan diets include vitamin B12, calcium, vitamin D, iron, omega-3 fatty acids, and zinc. As for all infants, for the first 4 to 6 months, vegetarian infants should solely receive breast milk or a commercial infant formula. Fortified infant cereal or firm tofu is an appropriate first complementary food. Either of these, along with breast milk or formula, can meet needs for protein, iron, and zinc. Additional foods are introduced with timing similar to that for nonvegetarians. A variety of nutrient-dense foods should be introduced by 1 year of age. Fortified soy or cow’s milk should be the primary beverage postweaning. Growth should be monitored, and toddlers should be served a diet that includes high-calorie, low-fiber foods if growth appears to be faltering. Practitioners can play important roles in assessing the growth of vegetarian infants and toddlers, helping families make appropriate feeding choices, evaluating the need for supplements, and assisting with planning meals that will meet the needs of infants and toddlers.

Perinatal programming of asthma: the role of gut microbiota

Perinatal programming, a dominant theory for the origins of cardiovascular disease, proposes that environmental stimuli influence developmental pathways during critical periods of prenatal and postnatal development, inducing permanent changes in metabolism. In this paper, we present evidence for the perinatal programming of asthma via the intestinal microbiome. While epigenetic mechanisms continue to provide new explanations for the programming hypothesis of asthma development, it is increasingly apparent that the intestinal microbiota plays an independent and potentially interactive role. Commensal gut bacteria are essential to immune system development, and exposures disrupting the infant gut microbiota have been linked to asthma. This paper summarizes the recent findings that implicate caesarean delivery, breastfeeding, perinatal stress, probiotics, and antibiotics as modifiers of infant gut microbiota in the development of asthma.

Evaluation of meat as a first complementary food for breastfed infants: impact on iron intake

The rationale for promoting the availability of local, affordable, non-fortified food sources of bioavailable iron in developing countries is considered in this review. Intake of iron from the regular consumption of meat from the age of 6 months is evaluated with respect to physiological requirements. Two major randomized controlled trials evaluating meat as a first and regular complementary food are described in this article. These trials are presently in progress in poor communities in Guatemala, Pakistan, Zambia, Democratic Republic of the Congo, and China.

The association of mode of delivery and common childhood illnesses

Participants enrolled in a randomized control trial (RCT) were eligible for this cross-sectional study to determine if children born via cesarean (C)-section had higher rates of common infectious diseases and change in normal daily activities due to illness than children born vaginally. The RCT collected parent-reported health information and mode of delivery was assessed during follow-up calls. Parent-reported rates of infectious sequelae and changes in daily activities were compared between C-section and vaginally delivered children. In total, 72.4% of the 522 children were delivered vaginally. After accounting for age, siblings, breast-feeding as an infant, and clustering within families, C-section delivered children had significantly higher rates of cumulative infectious diseases, lower respiratory tract infections, and cough than vaginally born children. Mode of delivery appears to have some lasting effect on child health 3 to 6 years after birth, specifically respiratory health. Further research is imperative to elucidate the causative effect of mode of delivery on child health.

The impact of perinatal probiotic intervention on gut microbiota: double-blind placebo-controlled trials in Finland and Germany

Specific probiotic combinations during early feeding, via the mother or incorporated in early formula-feeding, mold the intestinal microbiota composition in infants. The objective was to analyze the impact of probiotic administration to mother or infant on gut microbiota composition in 6-month-old Finnish and German infants. In Finland probiotics were given to mothers (n = 79) for 2 months prior to and 2 months after delivery. In Germany probiotics were started in infants (n = 81) at weaning, at the latest at 1 month of age, and continued for 4 months. A breast-fed group of 6-month-old infants (22 from Finland, 8 from Germany) were compared. Gut microbiota were analyzed by FCM-FISH and qPCR methods. In breast-fed infants a trend toward higher counts of bifidobacteria was detected in Finland (p = 0.097) as against Germany, where a more diverse microbiota was reflected in higher Akkermansia (p = 0.003), Clostridium histolyticum (p = 0.035) and Bacteroides-Prevotella (p = 0.027) levels and a higher percentage of Akkermansia (p = 0.004). Finnish LPR + BL999 intervention group (Lactobacillus rhamnosus LPR and Bifidobacterium longum BL999) had higher percentages of fecal Lactobacillus-Enterococcus (9.0% vs. 6.1% placebo, p = 0.003) and lower bifidobacteria levels (10.03 log cells/g vs. 10.68 log cells/g placebo, p = 0.018). Probiotic treatment had different impacts on gut microbiota composition in Finnish and German infants due to differences in mode of feeding and the early commensal microbiota. Probiotic treatment had different impacts on gut microbiota composition in Finnish and German infants due to differences in mode of feeding and the basic commensal microbiota.

Meat consumption is associated with less stunting among toddlers in four diverse low-income settings

BACKGROUND

Early growth faltering is common but is difficult to reverse after the first 2 years of life.

OBJECTIVE

To describe feeding practices and growth in infants and young children in diverse low-income settings prior to undertaking a complementary feeding trial.

METHODS

This cross-sectional study was conducted through the Global Network for Women's and Children's Health Research in Guatemala, Democratic Republic of Congo, Zambia, and Pakistan. Feeding questionnaires were administered to convenience samples of mothers of 5- to 9-month old infants and 12- to 24-month-old toddlers. After standardized training, anthropometric measurements were obtained from the toddlers. Following the 2006 World Health Organization Growth Standards, stunting was defined as length-for-age < -2SD, and wasting as weight-for-length < -2SD. Logistic regression was applied to evaluate relationships between stunting and wasting and consumption of meat (including chicken and liver and not including fish).

RESULTS

Data were obtained from 1,500 infants with a mean (+/- SD) age of 6.9 +/- 1.4 months and 1,658 toddlers with a mean age of 17.2 +/- 3.5 months. The majority of the subjects in both age groups were breastfed. Less than 25% of the infants received meat regularly, whereas 62% of toddlers consumed these foods regularly, although the rates varied widely among sites. Stunting rate ranged from 44% to 66% among sites; wasting prevalence was less than 10% at all sites. After controlling for covariates, consumption of meat was associated with a reduced likelihood of stunting (OR = 0.64; 95% CI, 0.46 to 0.90).

CONCLUSIONS

The strikingly high stunting rates in these toddlers and the protective effect of meat consumption against stunting emphasize the need for interventions to improve complementary feeding practices, beginning in infancy.

Red meat and a fortified manufactured toddler milk drink increase dietary zinc intakes without affecting zinc status of New Zealand toddlers

Evidence suggests that New Zealand (NZ) children are mildly zinc deficient and may respond to dietary change. A 20-wk randomized intervention trial was therefore conducted to determine whether an increased intake of red meat or consumption of a fortified manufactured toddler milk drink (FTMD, fortified with zinc and other micronutrients) would increase dietary zinc intakes and improve the biochemical zinc status of 12- to 20-mo-old NZ toddlers. Toddlers were randomized to a red meat intervention (n = 90), FTMD intervention (n = 45), or nonfortified milk placebo (n = 90). Study foods were provided. Adherence was assessed via monthly 7-d meat or milk recording diaries. Hair and serum zinc concentrations, and length and weight were measured at baseline and postintervention. Nutrient intakes were assessed via 3-d weighed food records at baseline, wk 4, and wk 18. At baseline, 38% of participants had low serum zinc concentrations despite seemingly adequate dietary zinc intakes (<4% below the Estimated Average Requirement). Dietary zinc intakes significantly increased by 0.8 mg/d (95% CI: 0.5, 1.1) in the meat group and 0.7 mg/d (95% CI: 0.2, 1.1) in the FTMD group compared with a decrease of -0.5 (95% CI: -0.8, -0.2) mg/d in the placebo group. No corresponding increases in serum or hair zinc concentrations were observed. Dietary zinc intakes achievable via interventions based on red meat or a FTMD are unlikely to improve biochemical zinc status in NZ toddlers. These results also question cutoffs used to define zinc deficiency in toddlers.

Probiotics and prebiotics: clinical effects in allergic disease

PURPOSE OF REVIEW

This paper summarizes recent publications on probiotics and prebiotics in allergic disease. It focuses on clinical studies of prevention or treatment of allergic disease.

RECENT FINDINGS

Studies suggest a role for certain probiotics (alone or with prebiotics) in the prevention of atopic eczema. Treatment during the prenatal period appears to be important for beneficial effects. The use of probiotics for the treatment of established allergic disease is less promising, despite some positive results. A Cochrane systematic review concluded that, when the results for the different probiotic strains used in clinical trials are pooled, probiotics are not effective for the treatment of eczema. There are fewer studies of prebiotics for the treatment or prevention of allergic disease, but data suggest that prebiotic-supplemented formulas may be effective for preventing eczema in infants at high risk of developing allergic disease when breast-feeding is not possible.

SUMMARY

Allergic diseases continue to increase in prevalence worldwide, and primary prevention of allergic disease has proved an elusive goal. Probiotic bacteria represent the most promising intervention for primary prevention that has been studied to date, and definitive intervention studies should now be a research priority.

Succession of microbial consortia in the developing infant gut microbiome

The colonization process of the infant gut microbiome has been called chaotic, but this view could reflect insufficient documentation of the factors affecting the microbiome. We performed a 2.5-y case study of the assembly of the human infant gut microbiome, to relate life events to microbiome composition and function. Sixty fecal samples were collected from a healthy infant along with a diary of diet and health status. Analysis of >300,000 16S rRNA genes indicated that the phylogenetic diversity of the microbiome increased gradually over time and that changes in community composition conformed to a smooth temporal gradient. In contrast, major taxonomic groups showed abrupt shifts in abundance corresponding to changes in diet or health. Community assembly was nonrandom: we observed discrete steps of bacterial succession punctuated by life events. Furthermore, analysis of ≈ 500,000 DNA metagenomic reads from 12 fecal samples revealed that the earliest microbiome was enriched in genes facilitating lactate utilization, and that functional genes involved in plant polysaccharide metabolism were present before the introduction of solid food, priming the infant gut for an adult diet. However, ingestion of table foods caused a sustained increase in the abundance of Bacteroidetes, elevated fecal short chain fatty acid levels, enrichment of genes associated with carbohydrate utilization, vitamin biosynthesis, and xenobiotic degradation, and a more stable community composition, all of which are characteristic of the adult microbiome. This study revealed that seemingly chaotic shifts in the microbiome are associated with life events; however, additional experiments ought to be conducted to assess how different infants respond to similar life events.

Iron intake and iron status in breastfed infants during the first year of life

BACKGROUND & AIMS

Breastfed infants may be at particular risk for iron deficiency because breast milk is low in iron. In a secondary analysis of data from a complementary feeding trial, indicators of iron status were examined, with particular focus on the development of iron status in those infants who were fully breastfed during the first 4 months of life.

METHODS

In this retrospective analysis of data from a randomized controlled trial infants were stratified according to their predominant milk diet during the first 4 months of life, a subgroup of breastfed infants (group BM, n=53) were compared with a subgroup of infants fed (iron-fortified) formula (group F, n=23). Dietary iron intake and indicators of iron status were analysed at 4 months of age (during the full milk feeding period), and during the complementary feeding period at 7 and 10 months of age.

RESULTS

Iron intake was low in the BM group, ranging below the Dietary Reference Intakes throughout the complementary feeding period, with the (estimated) bioavailable iron intake only just achieving the reference requirements. At 4 months, iron deficiency (ID, Ferritin <12.0 ng/mL) was observed in 3 infants in the BM group and in 1 infant in the F group; no infant developed iron deficiency anaemia (IDA, ID and Hb <10.5 g/dl). At 7 and at 10 months of age, iron status was adequate in all infants of the F group. In the BM group, at 7 (10) months of age, ID was diagnosed in 10 (11) infants and IDA was found in 2 (1) infants.

CONCLUSIONS

Healthy infants, fully breastfed at 4 months of age, demonstrated ID in about 21% and IDA in up to 6% during the second half of infancy while fed according to the paediatric dietary guidelines. This finding supports the recommendation that supplementation with bioavailable iron via complementary foods should be started early (4-6 months of age) in order to prevent iron deficiency during infancy.

Perinatal nutrition and immunity to infection

Epidemiological data provide strong evidence for a relationship between undernutrition and life-threatening infection in infants and children. However, the mechanisms that underlie this relationship are poorly understood. Through foetal life, infancy and childhood, the immune system undergoes a process of functional maturation. The adequacy of this process is dependent on environmental factors, and there is accumulating evidence of the impact of pre- and post-natal nutrition in this regard. This review outlines the impact of nutrition during foetal and infant development on the capacity to mount immune responses to infection. It provides an overview of the epidemiologic evidence for such a role and discusses the possible mechanisms involved.

Prebióticos, probióticos e simbióticos na prevenção e tratamento das doenças alérgicas

OBJETIVO: Avaliar o papel dos probióticos, prebióticos e simbióticos no equilíbrio do sistema imunológico do lactente, bem como seu efeito preventivo no desenvolvimento de doenças alérgicas na criança. FONTE DE DADOS: A partir do levantamento de todos os ensaios clínicos duplo-cegos e randômicos em seres humanos, publicados nos últimos cinco anos na base de dados Medline e que contivessem unitermos relacionados a prebióticos (oligossacarídeos), probióticos e simbióticos versus hipersensibilidade, analisou-se seu papel quanto à utilização em doenças alérgicas. SÍNTESE DE DADOS: Foram incluídos nesta revisão três trabalhos com prebióticos, os quais utilizaram a mistura GOS:FOS (9:1) em fórmulas infantis em lactentes nos primeiros meses de vida; 24 trabalhos com probióticos, sendo os micro-organismos utilizados na suplementação L. rhamnosus GG, B. lactis, L. casei, L. paracasei, L. reuteri, L. acidophilus, B. longum, B. breve e P. freudenreichii sp., e dois estudos com simbióticos. CONCLUSÕES: Apesar das evidências de benefícios da suplementação precoce de probióticos com algumas cepas específicas, prebióticos e simbióticos na prevenção da dermatite atópica, em crianças de alto risco para alergias, e do uso de probióticos no tratamento das dermatites atópicas moderadas e graves mediadas por IgE, há necessidade de ampliar os estudos quanto ao tempo de observação dos indivíduos suplementados, quanto à segurança e aos efeitos em longo prazo

Phenotypic and genomic diversity of Lactobacillus plantarum strains isolated from various environmental niches

Lactobacillus plantarum is a ubiquitous microorganism that is able to colonize several ecological niches, including vegetables, meat, dairy substrates and the gastro-intestinal tract. An extensive phenotypic and genomic diversity analysis was conducted to elucidate the molecular basis of the high flexibility and versatility of this species. First, 185 isolates from diverse environments were phenotypically characterized by evaluating their fermentation and growth characteristics. Strains clustered largely together within their particular food niche, but human fecal isolates were scattered throughout the food clusters, suggesting that they originate from the food eaten by the individuals. Based on distinct phenotypic profiles, 24 strains were selected and, together with a further 18 strains from an earlier low-resolution study, their genomic diversity was evaluated by comparative genome hybridization against the reference genome of L. plantarum WCFS1. Over 2000 genes were identified that constitute the core genome of the L. plantarum species, including 121 unique L. plantarum-marker genes that have not been found in other lactic acid bacteria. Over 50 genes unique for the reference strain WCFS1 were identified that were absent in the other L. plantarum strains. Strains of the L. plantarum subspecies argentoratensis were found to lack a common set of 24 genes, organized in seven gene clusters/operons, supporting their classification as a separate subspecies. The results provide a detailed view on phenotypic and genomic diversity of L. plantarum and lead to a better comprehension of niche adaptation and functionality of the organism.

Inflammatory bowel disease, gut bacteria and probiotic therapy

Crohn's disease (CD) and ulcerative colitis (UC) are the two major forms of inflammatory bowel disease (IBD) and both diseases lead to high morbidity and health care costs. Complex interactions between the immune system, enteric commensal bacteria and host genotype are thought to underlie the development of IBD although the precise aetiology of this group of diseases is still unknown. The understanding of the composition and complexity of the normal gut microbiota has been greatly aided by the use of molecular methods and is likely to be further increased with the advent of metagenomics and metatranscriptomics approaches, which will allow an increasingly more holistic assessment of the microbiome with respect to both diversity and function of the commensal gut microbiota. Studies thus far have shown that the intestinal microbiota drives the development of the gut immune system and can induce immune homeostasis as well as contribute to the development of IBD. Probiotics which deliver some of the beneficial immunomodulatory effects of the commensal gut microbiota and induce immune homeostasis have been proposed as a suitable treatment for mild to moderate IBD. This review provides an overview over the current understanding of the commensal gut microbiota, its interactions with the mucosal immune system and its capacity to induce both gut homeostasis as well as dysregulation of the immune system. Bacterial-host events, including interactions with pattern recognition receptors (PRRs) expressed on epithelial cells and dendritic cells (DCs) and the resultant impact on immune responses at mucosal surfaces will be discussed.

Probiotic safety in pregnancy: a systematic review and meta-analysis of randomized controlled trials of Lactobacillus, Bifidobacterium, and Saccharomyces spp

Our objective in this study was to review systematically the evidence for safety of Lactobacillus, Bifidobacterium and Saccharomyces spp. during pregnancy and to conduct a meta-analysis of randomized controlled trials (RCTs). Eleven databases were searched from inception to September 2007 for RCTs of probiotic use during pregnancy. Two independent reviewers searched databases. Random-effects models combined data. Eleven studies on Lactobacillus and/or Bifidobacterium examined 1505 patients for four outcomes with no data heterogeneity; no miscarriage data were reported. Five studies reported Caesarean section outcomes (OR 0.88; 95% CI 0.65 to 1.19). Six studies reported birth weight (weighted difference 45 g; 95% CI -181 to 271). Three studies reported gestational age (weighted difference 0.4 weeks; 95%CI -0.4 to 1.2). No malformations were reported in the probiotic group. No RCTs were available for Saccharomyces during pregnancy. Lactobacillus and Bifidobacterium had no effect on the incidence of Caesarean section, birth weight, or gestational age. The safety of Saccharomyces during pregnancy is unknown.

Influence of maternal bifidobacteria on the establishment of bifidobacteria colonizing the gut in infants

The aim of this study was to examine the influence of maternal intestinal and vaginal bifidobacteria on the establishment of bifidobacteria colonizing the gut in infants. Fecal samples from 110 healthy pregnant mothers within 1 mo before delivery and their babies at 1 mo of age and 100 vaginal swabs from the mother within 7 d before delivery were collected at a maternity hospital in Fukuoka city, Japan. The fecal and vaginal samples were assayed by PCR to detect Bifidobacterium species and by real-time PCR assays to estimate the bifidobacterial number. The detection of Bifidobacterium breve in the mothers' feces was significantly associated with increases in both the bifidobacterial counts and number of Bifidobacterium species in the babies' feces. In addition, a cesarean section was significantly associated with both a decrease in the counts and diversity of bifidobacteria in the babies' feces. The number of Bifidobacterium species detected in the vaginal swabs of mothers were not associated with either the bifidobacterial counts or the diversity of bifidobacteria in the babies' feces. The most important determinants of intestinal bifidobacteria in infants were the colonization of B. breve in the mothers' gut and vaginal delivery.

Prophylactic role of maternal administration of probiotics in the prevention of irritable bowel syndrome

Neonatal stress is a common early life event which alters the development of the endocrine and immune systems. Specifically, exposure to neonatal stress results in alterations to the hypothalamic-pituitary-adrenal (HPA) axis resulting in offspring who hyper-respond to stress in adulthood. Recently, this concept has been applied to the ontogeny of functional gastrointestinal (GI) disturbances such as irritable bowel syndrome (IBS). The high prevalence of this disorder and the ineffectiveness of current treatments results in high direct and indirect costs to the society. Recently, administration of probiotics to neonates has been used as a safe and cost-effective preventative strategy to revoke the long term unfavourable imprinting induced on the gastrointestinal system by early life stressors in animal models of human IBS. It is not as yet known however, whether maternal supplementary probiotics may also contribute to improved GI integrity and gut-associated immune functioning in stressed neonates, if these possible improvements persist into adulthood, or how this protective effect may be mediated. Our hypothesis is an attempt to link this proposed nutritional approach and its possible preventive effects against GI dysfunctions provoked by neonatal stress.

A Review of Interventions Based on Dietary Diversification or Modification Strategies with the Potential to Enhance Intakes of Total and Absorbable Zinc

Dietary diversification or modification has the potential to prevent deficiencies of zinc and other coexisting limiting micronutrients simultaneously, without risk of antagonistic interactions. In this review, we have addressed the following. The first section focuses on strategies with the potential to enhance intake and/or bioavailability of zinc, and includes interventions (with and without nutrition education) based on agriculture, production or promotion of animal-source foods through animal husbandry or aquaculture, and commercial and household processing strategies to enhance zinc absorption. Outcome indicators include intakes of foods or nutrients (although rarely zinc) and, in some cases, zinc status, or zinc-related functional responses. The next two sections address whether dietary diversification or modification can achieve increases in absorbable zinc that are sufficient to enhance zinc status or zinc-related functional responses in breastfed infants and toddlers and in older children and women of reproductive age. Evidence for the impact of dietary diversification or modification on behavior change and on nutritional status in the short and long term, and the possible role of modifying factors (e.g., baseline nutritional status, socioeconomic status, infection, sex, age, and life-stage group) is the emphasis of the next section. The following section highlights the evidence for three potential adverse effects of dietary diversification or modification: aflatoxin contamination from germinated cereals, loss of water-soluble nutrients, and displacement of breastmilk. Finally, an example of a dietary diversification or modification program (Homestead Food Production) developed and implemented by Helen Keller International is given, together with the critical steps needed to scale up dietary diversification or modification for programs and future research needs.

Probiotic supplementation in the first 6 months of life in at risk Asian infants--effects on eczema and atopic sensitization at the age of 1 year

BACKGROUND

The role of probiotics in allergy prevention remains uncertain but has been shown in some studies to have a possible protective effect on eczema.

OBJECTIVE

We aimed to assess the effect of probiotic supplementation in the first 6 months of life on eczema and allergic sensitization at 1 year of age in Asian infants at risk of allergic disease.

METHODS

A double-blind, placebo-controlled randomized clinical trial involving 253 infants with a family history of allergic disease was carried out. Infants received at least 60 mL of commercially available cow's milk formula with or without probiotic supplementation [Bifidobacterium longum (BL999) 1 x 10(7) colony forming unit (CFU)/g and Lactobacillus rhamnosus (LPR) 2 x 10(7) CFU/g] daily for the first 6 months. Clinical evaluation was performed at 1, 3, 6 and 12 months of age, with serum total IgE measurement and skin prick tests conducted at the 12-month visit. The primary and secondary end-points were eczema and allergen sensitization, respectively.

RESULTS

The incidence of eczema in the probiotic (22%) group was similar to that in the placebo group (25%) (P=0.53). The median Scoring Atopic Dermatitis score at 12 months was 17.10 (9.74) in the probiotic group and 11.60 (8.40) in the placebo group (P=0.17). The prevalence of allergen sensitization showed no difference (probiotic=24% vs. placebo=19%, P=0.26). The total IgE geometric mean (95% confidence interval) was 18.76 (12.54-24.98) kU/L in the probiotic group and 23.13 (16.01-30.24) kU/L in the placebo group (P=0.15). Atopic eczema (with sensitization) in the probiotic (7.3%) group was comparable to the placebo group (5.8%) (P=0.86).

CONCLUSION

Early life administration of a cow's milk formula supplemented with probiotics showed no effect on prevention of eczema or allergen sensitization in the first year of life in Asian infants at risk of allergic disease. Further work is needed to determine whether timing of supplementation, dose and probiotic strain are important considerations.

Sources of supplemental iron among breastfed infants during the first year of life

OBJECTIVES

Primary prevention of iron deficiency requires adequate iron intake. Although recommendations exist to promote adequate intake of iron among infants through iron-rich foods and iron supplements, few studies have examined adherence to these recommendations. Our objectives were to describe the consumption of iron-rich foods, oral iron supplements, and iron-fortified formula among US infants and to assess adherence to iron-intake recommendations.

METHODS

We analyzed data from the Infant Feeding Practices Study II, a longitudinal study of mothers and infants followed from late pregnancy through the first year of their infant's life. Mothers completed near-monthly questionnaires that assessed how frequently they fed their infants breast milk, formula, infant cereals, and meats in the previous 7 days and whether their infants were given an oral iron supplement > or = 3 times per week during the previous 2 weeks. We examined use of iron-fortified formula among infants who consumed formula; intake of cereal, meat, oral iron supplements, and formula among infants consuming any breast milk; and whether 6-month-old breastfed and mixed-fed (breast milk and formula) infants consumed sources of supplemental iron with recommended frequency.

RESULTS

At 6 months of age, 18% of the term breastfed and mixed-fed infants had not received infant cereal or meat in the previous 7 days, and 15% had not received infant cereal, meat, regular iron supplements, or formula; among solely breastfed infants, 23% had not received infant cereal, meat, or regular iron supplements. Fifty-eight percent of the mixed-fed infants and 70% of the solely breastfed infants received < 2 daily servings of infant cereal, meat, or formula combined and did not receive oral iron supplements > or = 3 times per week. Among preterm breastfed and mixed-fed infants, none received oral iron supplements > or = 3 times per week before 3 months of age, 2% received them at 3 months, and 13% received them at 10.5 months.

CONCLUSIONS

Our findings indicate that recommendations regarding iron intake among breastfed infants are not being followed by a substantial proportion of mothers.

Infant feeding and feeding transitions during the first year of life

OBJECTIVE

Infancy is a time of rapid transition from a diet of virtually nothing but milk (either breast milk or infant formula) to a varied diet from nearly all food groups being consumed on a daily basis by most infants. Despite various recommendations about infant feeding, little is known about actual patterns of feeding among US infants. This article documents transitions in infant feeding patterns across the first year of life and determinants of key aspects of infant feeding.

METHODS

Using data from the Infant Feeding Practices Study II, we analyzed responses to a 7-day food-recall chart that was administered every month. The sample size declined from 2907 at birth to 1782 at 12 months of age.

RESULTS

Although 83% of survey respondents initiated breastfeeding, the percentage who breastfed declined rapidly to 50% at 6 months and to 24% at 12 months. Many of the women who breastfed also fed their infants formula; 52% reported that their infants received formula while in the hospital. At 4 months, 40% of the infants had consumed infant cereal, 17% had consumed fruit or vegetable products, and <1% had consumed meat. Compared with infants who were not fed solid foods at 4 months, those who were fed solid foods were more likely to have discontinued breastfeeding at 6 months (70% vs 34%) and to have been fed fatty or sugary foods at 12 months (75% vs 62%).

CONCLUSIONS

Supplementing breast milk with infant formula while infants were still in the hospital was very common. Despite recommendations that complementary foods not be introduced to infants aged 4 months or younger, almost half of the infants in this study had consumed solid foods by the age of 4 months. This early introduction of complementary foods was associated with unhealthful subsequent feeding behaviors.

Nutrigenomics and personalized nutrition: science and concept

Diet and genomes interact. Nutrition has the most important life-long environmental impact on human health. While nutrigenetics addresses how an individual’s genetic makeup predisposes for dietary susceptibility, nutrigenomics asks how nutrition influences the expression of the genome. Nutrigenomics builds on the three omics disciplines transcriptomics, proteomics and metabolomics. They are a prerequisite for nutritional systems biology, the understanding of the interaction between food components and diet with cells, organs and the whole body. Personalized nutrition is a conceptual analog to personalized medicine. While there are food products available that address requirements or preferences of specific consumer groups, these products are based on empirical consumer science rather than on nutrigenomics and nutrigenetics. The latter two build the science foundation for understanding human variability in preferences, requirements and responses to diet, and may become the future tools for consumer assessment motivated by personalized nutritional counseling for health maintenance and disease prevention.

Host factors in amniotic fluid and breast milk that contribute to gut maturation

The gut represents a complex organ system with regional differences, which reflect selective digestive and absorptive functions that change constantly in response to bodily requirements and the outside milieu. As a barrier to the external environment, gut epithelium must be renewed rapidly and repeatedly. Growth and renewal of gut epithelial cells is dependent on controlled cell stimulation and proliferation by a number of signaling processes and agents, including gut peptides-both endogenous and exogenous sources. This cascade of events begins during fetal development; with the ingestion of amniotic fluid, this process is enhanced and continued during infancy and early childhood through the ingestion of human milk. Events influenced by amniotic fluid during fetal development and those influenced by human milk that unfold after birth and early childhood to render the gut mature are presented.

Human gut microbiota and bifidobacteria: from composition to functionality

The human gut is the home of an estimated 10(18) bacterial cells, many of which are uncharacterized or unculturable. Novel culture-independent approaches have revealed that the majority of the human gut microbiota consists of members of the phyla Bacteroidetes and Firmicutes. Nevertheless the role of bifidobacteria in gut ecology illustrates the importance of Actinomycetes and other Actinobacteria that may be underestimated. The human gut microbiota represents an extremely complex microbial community the collective genome of which, the microbiome, encodes functions that are believed to have a significant impact on human physiology. The microbiome is assumed to significantly enhance the metabolism of amino and glycan acids, the turnover of xenobiotics, methanogenesis and the biosynthesis of vitamins. Co-colonisation of the gut commensals Bifidobacterium longum and Bacteroides thetaiotaomicron in a murine model system revealed that the presence of bifidobacteria induced an expansion in the diversity of polysaccharides targeted for degradation by Bacteroides and also induced host genes involved in innate immunity. In addition, comparative analysis of individual human gut microbiomes has revealed various strategies that the microbiota use to adapt to the intestinal environment while also pointing to the existence of a distinct infant and adult-type microbiota.

Early differences in fecal microbiota composition in children may predict overweight

BACKGROUND

Experimental studies suggest that gut microbiota deviations predispose toward energy storage and obesity.

OBJECTIVE

We wanted to establish whether early gut microbiota composition can guide weight development throughout early childhood.

DESIGN

Overweight and obese children (n = 25) were selected from a prospective follow-up study at the age of 7 y and identified according to the International Obesity Task Force criteria. Normal-weight children (n = 24) were selected from the same cohort and matched for gestational age and body mass index at birth, mode of delivery, probiotic supplementation, duration of breastfeeding, use of antibiotics during infancy, and frequencies of atopic diseases and atopic sensitization. Early fecal microbiota composition was analyzed by fluorescent in situ hybridization (FISH) with microscopic and flow cytometry detection and by quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

The bifidobacterial numbers in fecal samples during infancy, as assessed by the FISH with flow cytometry, were higher in children remaining normal weight, [median: 2.19 x 10(9) cells/g (interquartile range: 1.10-5.28 x 10(9) cells/g)] than in children becoming overweight [1.20 x 10(9) cells/g (0.48-1.59x 10(9) cells/g); P = 0.02]. A similar tendency was found by FISH with microscopic detection and qRT-PCR. The microbiota aberrancy during infancy in children becoming overweight was also associated with a greater number of Staphylococcus aureus [0.64 x 10(6) cells/g (0.33-1.00 x 10(6) cells/g)] than in children remaining normal weight [0.27 x 10(6) cells/g (0.17-0.50 x 10(6) cells/g); P = 0.013].

CONCLUSION

Aberrant compositional development of the gut microbiota precedes overweight, offering new possibilities for preventive and therapeutic applications in weight management.

Complementary feeding: a commentary by the ESPGHAN Committee on Nutrition

This position paper on complementary feeding summarizes evidence for health effects of complementary foods. It focuses on healthy infants in Europe. After reviewing current knowledge and practices, we have formulated these conclusions: Exclusive or full breast-feeding for about 6 months is a desirable goal. Complementary feeding (ie, solid foods and liquids other than breast milk or infant formula and follow-on formula) should not be introduced before 17 weeks and not later than 26 weeks. There is no convincing scientific evidence that avoidance or delayed introduction of potentially allergenic foods, such as fish and eggs, reduces allergies, either in infants considered at increased risk for the development of allergy or in those not considered to be at increased risk. During the complementary feeding period, >90% of the iron requirements of a breast-fed infant must be met by complementary foods, which should provide sufficient bioavailable iron. Cow's milk is a poor source of iron and should not be used as the main drink before 12 months, although small volumes may be added to complementary foods. It is prudent to avoid both early (<4 months) and late (>or=7 months) introduction of gluten, and to introduce gluten gradually while the infant is still breast-fed, inasmuch as this may reduce the risk of celiac disease, type 1 diabetes mellitus, and wheat allergy. Infants and young children receiving a vegetarian diet should receive a sufficient amount ( approximately 500 mL) of breast milk or formula and dairy products. Infants and young children should not be fed a vegan diet.

Development of mucosal immune function in the intrauterine and early postnatal environment

PURPOSE OF REVIEW

There is recent evidence that immunological priming can start prenatally or in the very early life phase. This review summarizes recent progress in the field of early gut immunology with special attention to factors contributing to the intrauterine and early postnatal development of mucosal immune responses in the gut.

RECENT FINDINGS

Development and maturation of the fetal gut immune system occurs under close control of the maternal environment. Examples include maternal antibodies, cytokines, sCD14 molecules and bacterial antigens. Mouse experiments reveal that activated T cells can be detected already at birth in the fetal gut, which are supposed to be activated by signals from the maternal microbial gut flora. Human milk sCD14 is involved in the immunological priming of the developing gut immune system to Gram-negative bacteria and modulates the microbial recognition system of the gut. The development of food allergies is associated with consumption of food components like polyunsaturated fatty acids acting prenatally or in the early postnatal life span as immunomodulators.

SUMMARY

The new findings highlight the importance of very early life factors for the development of the mucosal immune functions of the gut. Therefore, the gut might be a new target to establish preventive strategies with regard to different immunologic disorders.

Effects of galactooligosaccharide and long-chain fructooligosaccharide supplementation during pregnancy on maternal and neonatal microbiota and immunity--a randomized, double-blind, placebo-controlled study

BACKGROUND

Galactooligosaccharides (GOS) and long-chain fructooligosaccharides (lcFOS) proliferate bifidobacteria in infant gut microbiota. However, it is not known how GOS and FOS influence the microbiota of pregnant women and whether a potential prebiotic effect is transferred to the offspring.

OBJECTIVES

We aimed to test how supplementation with GOS and lcFOS (GOS/lcFOS) in the last trimester of pregnancy affects maternal and neonatal gut microbiota. Variables of fetal immunity were assessed as a secondary outcome.

DESIGN

In a randomized, double-blind, placebo-controlled pilot study, 48 pregnant women were supplemented 3 times/d with 3 g GOS/lcFOS (at a ratio of 9:1) or maltodextrin (placebo) from week 25 of gestation until delivery. Percentages of bifidobacteria and lactobacilli within total bacterial counts were detected by fluorescent in situ hybridization and quantitative polymerase chain reaction in maternal and neonatal (days 5, 20, and approximately 182) stool samples. Variables of fetal immunity were assessed in cord blood by using flow cytometry and cytokine multiplex-array analysis.

RESULTS

The proportions of bifidobacteria in the maternal gut were significantly higher in the supplemented group than in the placebo group (21.0% and 12.4%, respectively; P = 0.026); the proportion of lactobacilli did not differ between the groups. In neonates, bifidobacteria and lactobacilli percentages, diversity and similarity indexes, and fetal immune parameters did not differ significantly between the 2 groups. Mother-neonate similarity indexes of bifidobacteria decreased over time.

CONCLUSIONS

GOS/lcFOS supplementation has a bifidogenic effect on maternal gut microbiota that is not transferred to neonates. The increased maternal bifidobacteria did not affect fetal immunity as measured by a comprehensive examination of cord blood immunity variables.

Maternal breast-milk and intestinal bifidobacteria guide the compositional development of the Bifidobacterium microbiota in infants at risk of allergic disease

BACKGROUND

The sources and the impact of maternal bacteria on the initial inoculum of the intestinal microflora of newborn infants remain elusive.

OBJECTIVE

To assess the association between maternal breast-milk and fecal bifidobacteria and infants' fecal bifidobacteria.

METHODS

Sixty-one mother-infant pairs were included, special emphasis being placed on the maternal allergic status. Bifidobacteria were analysed by a direct PCR method in fecal samples from mothers at 30-35 weeks of gestation and from infants at 1 month of age and from breast-milk samples 1 month post-partum.

RESULTS

Fecal Bifidobacterium adolescentis and Bifidobacterium bifidum colonization frequencies and counts among mother-infant pairs correlated significantly (P=0.005 and 0.02 for frequencies, respectively, and P=0.002 and 0.01 for counts, respectively). Only infants of allergic, atopic mothers were colonized with B. adolescentis. Each of the breast-milk samples contained bifidobacteria [median 1.4 x 10(3) bacterial cells/mL; interquartile range (IQR) 48.7-3.8 x 10(3)]. Bifidobacterium longum was the most frequently detected species in breast-milk. Allergic mothers had significantly lower amounts of bifidobacteria in breast-milk compared with non-allergic mothers [median 1.3 x 10(3) bacterial cells/mL (IQR 22.4-3.0 x 10(3)) vs. 5.6 x 10(3) bacterial cells/mL (1.8 x 10(3)-1.8 x 10(4)), respectively, (P=0.004)], and their infants had concurrently lower counts of bifidobacteria in feces [3.9 x 10(8) bacterial cells/g (IQR 6.5 x 10(6)-1.5 x 10(9)) in infants of allergic mothers, vs. 2.5 x 10(9) bacterial cells/g (6.5 x 10(8)-3.2 x 10(10)) in infants of non-allergic mothers, P=0.013].

CONCLUSIONS

Breast-milk contains significant numbers of bifidobacteria and the maternal allergic status further deranges the counts of bifidobacteria in breast-milk. Maternal fecal and breast-milk bifidobacterial counts impacted on the infants' fecal Bifidobacterium levels. Breast-milk bacteria should thus be considered an important source of bacteria in the establishment of infantile intestinal microbiota.

Molecularly assessed shifts of Bifidobacterium ssp. and less diverse microbial communities are characteristic of 5-year-old allergic children

The composition of intestinal microbiota and the Bifidobacterium group community in 20 allergic and 20 nonallergic 5-year-old children was visualized by PCR-denaturing gradient gel electrophoresis (DGGE). The number of dominant bands in the DGGE profiles was smaller in allergic children than in nonallergic children (P<0.001). Allergic children mainly formed a single group upon cluster analysis, whereas nonallergic children were divided between four different groups. In allergic children the Bifidobacterium adolescentis species prevailed, and in nonallergic children the Bifidobacterium catenulatum/pseudocatenulatum prevailed (P=0.01 and P=0.01, respectively). The less diverse composition of intestinal microbiota and prevalence of particular species of Bifidobacterium were characteristic of allergic children even at the age of 5 years.

Iron requirements, absorption and metabolism in infancy and childhood

PURPOSE OF REVIEW

Iron deficiency is a significant public health problem in young children due to their high iron requirements, and iron supplements are therefore often recommended. During the time period in focus for this review (2005-2006), there have been additional advances in our understanding of the molecular mechanisms of iron absorption and metabolism. It has also been suggested that iron supplements may have adverse effects in children.

RECENT FINDINGS

Recently discovered molecules, for example hepcidin, lactoferrin receptor and heme carrier protein may be important for iron metabolism in children. There are possible metabolic interactions between iron and several other minerals. Many studies show that iron deficiency in young children is associated with impaired neurodevelopment but it is not clear whether this can be prevented by iron supplementation. Oral iron supplements given to young children in malarious regions may lead to increased risk of death or severe infections, especially in those who are iron replete.

SUMMARY

More research is needed to identify those children who will benefit from iron supplementation and to better determine iron requirements during early life. Clinical trials should include functional outcomes. Better knowledge about molecular mechanisms and nutrient interactions may lead to new diagnostic tests and preventive strategies.

Zinc deficiency: a special challenge

In the development and testing of programs designed to improve complementary feeding globally, local nonfortified food-based solutions comprise an important strategy for the foreseeable future. These solutions are especially vital for the rural poor of less-developed countries. Zinc is notable among individual nutrients that have been designated as "problem" nutrients, adequate intake of which is difficult from complementary foods without fortification. This article considers the potential role of meat +/- liver in addressing this apparent problem. In a recent Colorado study, beef and cereal have been determined to be equally acceptable between age 5-7 mo as first and regular complementary foods. Average intake and absorption of Zn from beef by 7 mo of age, together with the modest intake/absorption of Zn from breast milk at that age, were adequate to meet average dietary and physiologic zinc requirements, respectively. Barriers to acceptability and availability of affordable meat are considered, but these are neither universal nor irresolvable in all populations.

Food choices to meet nutritional needs of breast-fed infants and toddlers on mixed diets

The primary focus of this review is considerations for complementary feedings to meet micronutrient needs of infants aged 6-24 mo who are continuing with breast-feeding and minimal or no formula. The World Health Organization recommends initiation of complementary feeding to breast-fed infants at approximately 6 mo of age. Whether complementary foods will meet nutrient needs will depend on the types of food selected. One criterion for the selection of complementary foods is that they be rich sources of zinc and iron because both of these essential micronutrients are critical for normal growth and development, and requirements are not met by exclusive breast-feeding after approximately 6 mo. For an exclusively breast-fed 7-mo-old infant, human milk provides approximately 0.5 mg of zinc, and a little over half of that is absorbed. Adding some cereal can increase zinc intake modestly but will fall short of providing the estimated physiologic requirement because adaptive mechanisms are inadequate to compensate for moderately low zinc intake. Maize, wheat, rice, and roots are also relatively low in zinc and have the added factor of a high phytate-to-zinc molar ratio, which makes the zinc less bioavailable. Meats and liver have greater zinc and iron concentrations than unfortified plant foods and have been shown to have good acceptance by 7-mo-old infants. In contrast to current practices in both developed and developing countries, meats should be considered as an early complementary food for breast-fed infants to provide essential micronutrients.

Complementary feeding: clinically relevant factors affecting timing and composition

Exclusive breastfeeding for the first 6 mo of life followed by optimal complementary feeding are critical public health measures for reducing and preventing morbidity and mortality in young children. Clinical factors, such as birth weight, prematurity, and illness, that affect the iron and zinc requirements of younger infants are discussed. Maternal diet and nutritional status do not have a strong effect on the mineral content of human milk, but physiologic changes in milk and the infants' status determine the dependence of the infant on complementary foods in addition to human milk to meet iron and zinc requirements after 6 mo. The nature of zinc absorption, which is suitably characterized by saturation response modeling, dictates that plant-based diets, which are low in zinc, are associated with low absolute daily absorbed zinc, which is inadequate to meet requirements. Foods with a higher zinc content, such as meats, are much more likely to be sufficient to meet dietary requirements. Current plant-based complementary feeding patterns for older fully breastfed infants in both developed and developing countries pose a risk of zinc deficiency. The strong rationale for the potential benefits of providing meat as an early complementary food, and the examples of successful intervention programs, provide potent incentives to pursue broader implementation programs, with concurrent rigorous evaluation of both efficacy and effectiveness.

Zinc supplementation does not affect growth, morbidity, or motor development of US term breastfed infants at 4-10 mo of age

BACKGROUND

It has been documented that growth patterns differ between breastfed and formula-fed infants. Some investigators have suggested that these differences may be related to differences in zinc nutriture.

OBJECTIVE

The objective of this study was to examine the effect of zinc supplementation on growth, morbidity, and motor development in healthy, term, breastfed infants.

DESIGN

We conducted a randomized double-blind intervention comparing zinc supplementation (5 mg/d as zinc sulfate) with placebo in breastfed infants aged 4-10 mo. Growth and indexes of body composition and gross motor development were measured monthly from 3 to 10 mo. Morbidity data were collected weekly.

RESULTS

Eighty-five infants were enrolled, and 70 completed the study. The baseline characteristics, attained weight or length at 10 mo, growth velocity, gross motor development, and morbidity did not differ significantly between groups, even after control for potentially confounding variables.

CONCLUSIONS

The dietary zinc intake of these breastfed infants appeared to be adequate, given that zinc supplementation did not affect growth, development, or risk of infection (although sample size for detection of differences in development or infection was limited). Previously described differences in growth between breastfed and formula-fed infants in such populations do not appear to be due to differences in zinc nutriture.