Effects of Bifidobacterium lactis HN019 and prebiotic oligosaccharide added to milk on iron status, anemia, and growth among children 1 to 4 years old

Gut microbiota and childhood malnutrition: Understanding the link and exploring therapeutic interventions

Childhood malnutrition is a metabolic condition that affects the physical and mental well-being of children and leads to resultant disorders in maturity. The development of childhood malnutrition is influenced by a number of physiological and environmental factors including metabolic stress, infections, diet, genetic variables, and gut microbiota. The imbalanced gut microbiota is one of the main environmental risk factors that significantly influence host physiology and childhood malnutrition progression. In this review, we have evaluated the gut microbiota association with undernutrition and overnutrition in children, and then the quantitative and qualitative significance of gut dysbiosis in order to reveal the impact of gut microbiota modification using probiotics, prebiotics, synbiotics, postbiotics, fecal microbiota transplantation, and engineering biology methods as new therapeutic challenges in the management of disturbed energy homeostasis. Understanding the host-microbiota interaction and the remote regulation of other organs and pathways by gut microbiota can improve the effectiveness of new therapeutic approaches and mitigate the negative consequences of childhood malnutrition.

Growth Patterns of 11-29-Month-Old Children Consuming Young Child Formula: Secondary Analysis of a Randomized, Controlled Study

INTRODUCTION

The impact of young child formula (YCF) consumption on children's growth, particularly under suboptimal conditions, has scarcely been studied. In the current study, weight-for-age (WAZ), length-for-age (LAZ), and BMI-for-age (BAZ) z-score development was evaluated in children from five different countries (n = 668) who participated in a double-blind, randomized, controlled trial.

METHODS

The children (1-3 years old) were randomized to one of two intervention YCFs (with presence or absence of prebiotics and n-3 LCPUFAs) during 52 weeks of intervention. Additional stratified analyses evaluated the growth patterns of underweight, overweight, or stunted children.

RESULTS

No apparent differences in anthropometric measurements were observed between the intervention groups. In both YCF intervention groups, mean WAZ, LAZ and BAZ development was indicative of adequate growth during the intervention period. Stratified analyses showed stable WAZ and BAZ development among children with a healthy weight or overweight at baseline. Among underweight and stunted children, normalization in mean weight (∼1 SD) and length (∼0.8 SD) gain, respectively, was observed.

CONCLUSION

The current study suggests that consumption of YCF, either or not containing prebiotics and n-3 LCPUFAs, is associated with adequate growth among young children. This association may depend on the child's baseline nutritional status. Future studies to assess the potential role of YCF in supporting adequate weight/length gain among children at risk for undernutrition are warranted.

Gut Microbiome-Targeted Nutrition Interventions and Growth among Children in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

Background

Childhood malnutrition is a public health challenge of much interest and concern globally. However, a perturbed gut microbiome (GM) may limit some nutrition interventions' effects among healthy children with undernutrition.

Objectives

This review aimed to evaluate the effects of GM-targeted nutrition interventions on growth outcomes among children (0-59 mo) using published studies in low- and middle-income countries.

Methods

The methods were guided by the Cochrane methodology. The literature search was conducted to include articles published from inception to July 2023 in PubMed, Google Scholar, and Cochrane Databases. We identified and included 35 studies among 11,047 children. The analysis was conducted considering various growth parameters in the qualitative synthesis and weight gain (kg) in the meta-analysis.

Results

In the qualitative synthesis, 55.6% of prebiotics, 66.7% of probiotics, 71.4% of synbiotics, and 28.6% of "microbiome complementary feed" studies had significant effects on growth outcomes. Also, prebiotics had more studies with significant effects among healthy children, whereas probiotics, synbiotics, and "microbiome complementary feeds" had more studies with significant effects among children with undernutrition. Nineteen studies were included in the meta-analyses, of which 7 (36.8%) measured GM outcomes. The meta-analysis showed that prebiotics exhibited heterogeneity but had significant effects on weight in the intervention as compared with the control (mean difference [MD]: 0.14 kg; 95% CI: 0.02, 0.25; I2 = 63%, P = 0.02; 4 studies, n = 932). Probiotics had significant effects on weight in the intervention (MD: 0.15 kg; 95% CI: 0.06, 0.25; I2 = 42%, P = 0.05; 8 studies, n = 2437) as compared to the control. However, synbiotics (MD: 0.26 kg; 95% CI: -0.04, 0.56; I2 = 41%, P = 0.17; 4 studies, n = 1896] and "microbiome complementary feed" (MD: -0.03 kg; 95% CI: -0.18, 0.11; I2 = 0%, P = 0.60; 3 studies, n = 733] had no significant effects on weight in the intervention as compared with control.

Conclusions

Although probiotics and synbiotics may be effective at enhancing growth among children, the selection of interventions should be contingent upon health status.This trial was registered at www.crd.york.ac.uk/prospero/ as CRD42023434109.

Probiotic Supplementation for Promotion of Growth in Undernourished Children: A Systematic Review and Meta-Analysis

OBJECTIVES

Probiotic supplementation has been proposed as a therapeutic intervention to improve growth outcomes in children with undernutrition. The objective of this review is to synthesize the current evidence on probiotic supplementation for promotion of growth in undernourished children.

METHODS

We searched MEDLINE, Cochrane CENTRAL, CINAHL, Embase, LILACS, and Scopus for randomized controlled trials (RCTs) that administered probiotics or eligible comparators to undernourished children below 5 years of age. Our primary outcomes of interest were weight-for-age, height-for-age, and weight-for-height at the longest follow-up points reported. Random-effects meta-analysis was used to calculate standardized mean differences (SMD) for continuous outcomes and risk ratios for dichotomous outcomes. The Grading of Recommendations Assessment, Development and Evaluation criteria were used to assess certainty of the evidence.

RESULTS

Nine RCTs with 5295 children in total were included. Durations of treatment ranged from 1 month to 1 year. Pooled analyses from 7 studies showed that probiotics may have little to no effect on weight-for-age (SMD 0.05 standard deviation [SD], 95% CI: -0.04 to 0.13, n = 2115 children; low-certainty evidence) and height-for-age (SMD -0.04 SD, 95% CI: -0.14 to 0.07, n = 1357 children; low-certainty evidence). The evidence was very uncertain about the effect on weight-for-height.

CONCLUSIONS

Probiotics may have little to no effect on anthropometry in undernourished children, though there is considerable heterogeneity among the trials reviewed thus far. The interaction between gut microbiota and human nutrition is complex, and further research is needed to determine how the gut microbiome may contribute to undernutrition and how probiotics may affect growth in this vulnerable population.

Synbiotic supplement for treatment of iron deficiency anaemia in haemodialysis patients: A randomized controlled trial

BACKGROUND

There is evidence that probiotics can increase the availability of iron. The aim of current study was to determine the effects of synbiotic supplementation on the haematological parameters and anaemia in haemodialysis patients.

METHODS

This study was a randomized, double-blind, placebo-controlled trial. Fifty patients were randomly selected from the haemodialysis section of Vaseii Hospital, Sabzevar, Iran. Subjects in the symbiotic and control groups received 2 capsules of synbiotic supplement or placebo, respectively, once a day for 8 weeks. Blood samples were divided into two test tubes in equal volumes. Blood haemoglobin, haematocrit, transferrin saturation, red blood cells (RBCs), and total iron binding capacity (TIBC) were measured with auto-analyser. Ferritin was determined using Sandwich enzyme-linked immunosorbent assay (ELISA).

RESULTS

Twenty tree patients in each group completed the study. Significant results were recorded in synbiotic groups regarding the concentration of blood haemoglobin, haematocrit, transferrin saturation, the number of RBCs, and serum ferritin compare to placebo group (P < .05). At the end of week 8, TIBC significantly decreased in synbiotic than placebo group (P < .05).

CONCLUSION

Synbiotic supplementation could be a safe and promising candidate in improving anaemia in CKD patients.

Effects of probiotic and synbiotic supplementation on ponderal and linear growth in severely malnourished young infants in a randomized clinical trial

Severe acute malnutrition (SAM) is a major global public health problem. We aimed to assess the effects of probiotic and synbiotic supplementation on rate of weight gain and change in length in young SAM infants. This study was substudy of a single-blind randomized clinical trial (NCT0366657). During nutritional rehabilitation, 67 <6 months old SAM infants were enrolled and randomized to receive either probiotic (Bifidobacterium. infantis EVC001) or synbiotic (B. infantis EVC001 + Lacto-N-neotetraose [LNnT]) or placebo (Lactose) for four weeks and were followed for four more weeks after supplementation. In multivariable linear regression model, the mean rate of weight gain in the probiotic arm compared to placebo was higher by 2.03 unit (P < 0.001), and 1.13 unit (P = 0.030) in the synbiotic arm. In linear mixed-effects model, mean WAZ was higher by 0.57 unit (P = 0.018) in probiotic arm compared to placebo. Although not statistically significant, delta length for age z score (LAZ) trended to be higher among children in probiotc (β = 0.25) and synbiotic (β = 0.26) arms compared to placebo in multivariable linear regression model. Our study describes that young SAM infants had a higher rate of weight gain when supplemented with probiotic alone, compared to their counterparts with either synbiotic or placebo.

Effect of Fortified Formula on Growth and Nutritional Status in Young Children: A Systematic Review and Meta-Analysis

Previous reviews of the effect of young child formulas on health outcomes in infants and toddlers have been inconclusive. In this study, we undertook a contemporary synthesis of studies investigating the effects of consuming fortified milk beverages (compared to cow’s milk or unfortified comparator formula) on growth and/or nutritional status in children 1−3 years of age. Five electronic databases were searched (PubMed, Web of Science, Scopus, ProQuest, and Cochrane Library) for randomised controlled trials comparing fortified milk against control milk in young children (9−48 months), published between January 1990 and June 2022. Outcomes were growth, body composition, biochemical markers, and/or nutritional status. Mean differences (MD) were pooled using random-effects meta-analysis where there were ≥3 studies. The risk of bias was assessed using the Cochrane Risk of Bias 2.0 tool. Nineteen articles (12 studies; n = 4795) met the inclusion criteria. Heterogeneity was substantial, likely attributable to considerable variation in study characteristics. Fortified milk was associated with increased weight gain (MD = 0.14 kg [95% CI 0.06, 021], p = 0.0003) compared with control milk. Subgroup analyses demonstrated increases in weight in lower-income countries, and in studies with intervention periods > 6 months. There were no effects of fortified milks on other anthropometric measures. Haemoglobin (MD = 3.76 g/L [95% CI 0.17, 7.34], p = 0.04) and ferritin (MD = 0.01 nmol/L [95% CI 0.00, 0.02], p = 0.02) concentrations were increased in infants consuming fortified milks. Fortified milk beverages appear to offer a safe and acceptable source of complementary nutrition as a short-term strategy for addressing nutritional deficits and may modestly promote weight gain in vulnerable populations when provided for periods > 6 months. This study was prospectively registered with PROSPERO (CRD42022339920) and funded by the Infant Nutrition Council.

Comparison of two probiotics in follow-on formula: Bifidobacterium animalis subsp. lactis HN019 reduced upper respiratory tract infections in Chinese infants

A randomised, double-blind, placebo-controlled trial was performed to investigate the health benefits of probiotic bacteria in infants when delivered in a follow-on infant formula. The study was conducted in Fuyang (Anhui Province, China) during winter and enrolled 192 healthy infants aged six to 12 months. Infants received one of three follow-on formulae daily for 12 weeks: supplemented with 106 cfu/g Bifidobacterium animalis subsp. lactis HN019 (n=64); 106 cfu/g Lacticaseibacillus rhamnosus HN001 (n=64); or without added probiotics (n=64). The primary endpoint was physician-confirmed bacterial or viral infections during the treatment period. Secondary endpoints included parentally reported (confirmed and unconfirmed) infections; antiviral or antibiotic treatments, and hospitalisation; stool frequency and consistency; infant growth; infant temperament; and adverse events. There were 8 cases of confirmed infection, all upper respiratory tract infections (URTIs). Confirmed URTIs were observed in 9.4% of the control group, compared to 3.1% in the HN001 group (P=0.273), and 0.0% in the HN019 group (P=0.028). A similar trend was observed for parentally reported URTIs, with 25.0% in the control group, compared with 14.1% in the HN001 group (P=0.119) and 9.4% in the HN019 group (P=0.019). No infants in the HN019 group were prescribed antibiotics or antivirals, compared with 3 (4.7%) in the HN001 group and 7 (10.9%) in the control group. No infants required hospitalisation. The probiotic-containing formulae were well-tolerated: there were no cases of diarrhoea or differences in stool frequency or characteristics, no differences in infant growth or temperament, and no treatment-related adverse events. This study directly compared the benefits of two different probiotics when added to follow-on infant formula at 106 cfu/g and consumed over a 12-week period. While HN001 showed trends toward reduced infections, HN019 showed better performance in terms of significantly reduced incidence of both physician-confirmed and parentally reported URTIs, and antibiotic/antiviral use compared to a control in Chinese infants. The trial is registered at ClinicalTrials.gov (NCT01724203).

Fecal Iron Measurement in Studies of the Human Intestinal Microbiome

Iron is an essential micronutrient for humans and their intestinal microbiota. Host intestinal cells and iron-dependent bacteria compete for intraluminal iron, so the composition and functions of the gut microbiota may influence iron availability. Studies of the effects of the microbiota or probiotic interventions on host iron absorption may be particularly relevant to settings with high burdens of iron deficiency and gastrointestinal infections, since inflammation reduces iron bioavailability and unabsorbed intraluminal iron may modify the composition of the microbiota. The quantification of stool iron content may serve as an indicator of the amount of intraluminal iron to which the intestinal microbiota is exposed, which is particularly relevant for studies of the effect of iron on the intestinal microbiome, where fecal samples collected for purposes of microbiome characterization can be leveraged for stool iron analysis. However, few studies are available to guide researchers in the selection and implementation of stool iron assays, particularly because cross-comparison of available methods is limited in literature. This review aims to describe the available stool iron quantification methods and highlight their potential application in studies of iron-microbiome relationships, with a focus on pediatric research. MS-based methods offer high sensitivity and precision, but the need for expensive equipment and the high per-sample and maintenance costs may limit their widespread use. Conversely, colorimetric assays offer lower cost, ease of use, and rapid turnaround times but have thus far been optimized primarily for blood-derived matrices rather than stool. Further research efforts are needed to validate and standardize methods for stool iron assessment and to determine if the incorporation of such analyses in human microbiome studies 1) yields insights into the interactions between intestinal microbiota and iron and 2) contributes to the development of interventions that mitigate iron deficiency and promote a healthy microbiome.

The Concept of Postbiotics

The scientific community has proposed terms such as non-viable probiotics, paraprobiotics, ghostbiotics, heat-inactivated probiotics or, most commonly, postbiotics, to refer to inanimate microorganisms and/or their components that confer health benefits. This article addresses the various characteristics of different definitions of ‘postbiotics’ that have emerged over past years. In 2021, the International Scientific Association for Probiotics and Prebiotics (ISAPP) defined a postbiotic as “a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host”. This definition of postbiotic requires that the whole or components of inactivated microbes be present, with or without metabolic end products. The definition proposed by ISAPP is comprehensive enough to allow the development of postbiotics from different microorganisms, to be applied in different body sites, encouraging innovation in a promising area for any regulatory category and for companion or production animals, and plant or human health. From a technological perspective, probiotic products may contain inanimate microorganisms, which have the potential to impart a health benefit. However, their contribution to health in most cases has not been established, even if at least one probiotic has been shown to confer the same health benefit by live or inanimate cells.

Gut Microbiota Modulation of Moderate Undernutrition in Infants through Gummy Lactobacillus plantarum Dad-13 Consumption: A Randomized Double-Blind Controlled Trial

Undernutrition is associated with gut microbiota unbalance, and probiotics are believed to restore it and improve gut integrity. A randomized double-blind controlled trial was conducted to evaluate the efficacy of gummy L. plantarum Dad-13 (10^8-9 CFU/3 g) to prevent the progression of severe undernutrition. Two groups of moderate undernutrition infants were involved in this study, namely the placebo (n = 15) and probiotics (n = 15) groups, and were required to consume the product for 50 days. 16S rRNA sequencing and qPCR were used for gut microbiota analysis, and gas chromatography was used to analyze Short-Chain Fatty Acid (SCFA). The daily food intake of both groups was recorded using food records. Our results revealed that the probiotic group had better improvements regarding the anthropometry and nutritional status. In addition, L. plantarum Dad-13 modulated the butyric acid-producing bacteria to increase and inhibit the growth of Enterobacteriaceae. This gut modulation was associated with the increment in SCFA, especially total SCFA, propionic, and butyric acid. The number of L. plantarum was increased after the probiotic intervention. However, L. plantarum Dad-13 was not able to change the alpha and beta diversity. Therefore, L. plantarum Dad-13 has been proven to promote the growth of beneficial bacteria.

Ameliorating effects of probiotics on alterations in iron homeostasis and inflammation in COVID-19

Introduction

The coronavirus disease (COVID-19) is caused by the severe acute syndrome coronavirus-2 (SARS-COV-2) and still threatens human life. This pandemic is still causing increased mortality throughout the world. Many recent studies have been conducted to discover the pathophysiology of this virus.

Material and methods

However, in this narrative review, we attempted to summarize some of the alterations in physiological pathways that were evident in this viral invasion. Excessive inflammation that progresses to cytokine storm, changes in humoral and cell-mediated immunity, and observed alterations in iron metabolism are included in the pathogenesis of the virus. Iron homeostasis disturbances may persist for more than two months after the onset of COVID-19, which may lead to reduced iron bioavailability, hypoferremia, hyperferritinemia, impaired hemoglobin, and red blood cell synthesis. Furthermore, hypoferriemia may impair immune system function. Until now, the traditional treatments discovered are still being tried.

Results

However, using probiotics as an adjuvant was shown to have beneficial effects on both iron homeostasis and immunity in COVID-19. Herein, we discussed the possible mechanisms achieved by probiotics to ameliorate iron and immunity changes based on the available literature.

Conclusion

We concluded that supplementing probiotics with conventional therapy may improve COVID-19 symptoms and outcomes. Taking into consideration the use of good quality probiotics and appropriate dosage, undesirable effects can be avoided.

Probiotic Supplementation for Promotion of Growth in Children: A Systematic Review and Meta-Analysis

Probiotics are commonly prescribed to promote a healthy gut microbiome in children. Our objective was to investigate the effects of probiotic supplementation on growth outcomes in children 0-59 months of age. We conducted a systematic review and meta-analysis which included randomized controlled trials (RCTs) that administered probiotics to children aged 0-59 months, with growth outcomes as a result. We completed a random-effects meta-analysis and calculated a pooled standardized mean difference (SMD) or relative risk (RR) and reported with a 95% confidence interval (CI). We included 79 RCTs, 54 from high-income countries (HIC), and 25 from low- and middle-income countries (LMIC). LMIC data showed that probiotics may have a small effect on weight (SMD: 0.26, 95% CI: 0.11-0.42, grade-certainty = low) and height (SMD 0.16, 95% CI: 0.06-0.25, grade-certainty = moderate). HIC data did not show any clinically meaningful effect on weight (SMD: 0.01, 95% CI: -0.04-0.05, grade-certainty = moderate), or height (SMD: -0.01, 95% CI: -0.06-0.04, grade-certainty = moderate). There was no evidence that probiotics affected the risk of adverse events. We conclude that in otherwise healthy children aged 0-59 months, probiotics may have a small but heterogenous effect on weight and height in LMIC but not in children from HIC.

Gut Microbiota-Targeted Nutritional Interventions Improving Child Growth in Low- and Middle-Income Countries: A Systematic Review

The objective of this systematic literature review was to evaluate the efficacy of probiotic, prebiotic, and synbiotic interventions compared with control on improving growth outcomes of children living in low- and middle-income countries (LMICs). Probiotics had a beneficial effect on ≥1 of the growth outcomes in 5 out of the 11 included studies. Of these, 3 studies were conducted in undernourished children, 1 in healthy children, and 1 in children without a described health status. No effect of prebiotics on growth outcomes was seen in the 4 included studies. Synbiotics had a beneficial effect on growth outcomes in 3 out of 4 studies. Although a limited number of studies with high heterogeneity indicate that probiotics and synbiotics may have the potential to improve the growth of both undernourished and healthy children living in LMICs, more research is needed to confirm the observed effects. This review was registered at www.crd.york.ac.uk/prospero/ as CRD42020212998.

Effects of potential probiotic strains LBKV-3 on Immune Cells responses in Malnutrite children: a double-blind, randomized, Controlled trial

This study investigated the phagocytic cell response in malnourished children after oral feeding of a fermented product containing clinically proven probiotic strains of Lactobacillus acidophilus, LBKV-3. The bacterial strain is used as a probiotic for humans to test its effect on immune cell activity in undernourished children below 8 years of age. To study the immune cell activity, implantation abilities of the culture in the GI tract of malnourished children, forty-five children of 6-7 and 7-8 years were randomly selected and distributed in three groups, each comprising 15 children in each of the age group. The test group of the children was receiving 100 g product volunteers/day of freshly prepared probiotic acidophilus milk containing 10⁷ cfu/g of culture. The control group was receiving 100 g freshly prepared "dahi" containing 10⁷ cfu/g of the LAB while the blank group of the volunteers was receiving thermal processed (85° C/30 min) buffalo milk containing 5% fat and 10% SNF at the rate of 100 ml/day/volunteer. Feeding trial was continued for 12 weeks. Blood samples were collected at W2, W4, W8, and W12. The blood serum samples were analyzed for monocytes, neutrophils, basophils, and lymphocytes by BC-3000 + Auto Hematology Analyzer. In conclusion, consumption of PAM increased the proportion of immune cells, including monocytes, neutrophils, basophils, and lymphocytes, as well as their phagocytic activity in all age groups but proportion was significant in the test group of 7-8 years. The effects were higher during W12 compared to W2, W4, and W8, which suggest regulation of the immune system.

Synbiotic Fermented Milk with Double Fortification (Fe-Zn) as a Strategy to Address Stunting: A Randomized Controlled Trial among Children under Five in Yogyakarta, Indonesia

Stunting is one of the public health problems that has yet to be solved in Indonesia. This study developed synbiotic fermented milk with iron and zinc fortification that was then tested in a clinical setting. The product was made from skimmed milk and fructooligosaccharides (FOS) and fermented with Lactobacillus plantarum. A sample of 94 stunted children under five years old were randomly assigned to intervention or control groups. The intervention group received double-fortified synbiotic milk, while the control group drank non-fortified milk. After three months, the number of normal children in both groups, according to weight- or height-for-age z-score category, was found to be increasing. However, the difference between the two groups was not significant (p > 0.05). The study suggests that fermented milk may have a good effect on child growth. Further research is needed to deepen the potency of synbiotic fermented milk for stunted children.

Effects of probiotics and synbiotics on diarrhea in undernourished children: Systematic review with meta-analysis

BACKGROUND

Undernutrition predisposes children to a greater incidence and duration of diarrhea. No review and meta-analysis have yet been conducted to assess effectiveness of probiotics and synbiotics in undernourished children.

AIMS

To assess the effectiveness of probiotics and synbiotics on diarrhea in undernourished children.

METHODS

Randomized, double-blind, placebo-controlled trials evaluating the effects of probiotics and synbiotics on diarrhea in undernourished children were searched from 1990 to May 2020. Recommendations of the Cochrane Handbook and the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement were followed.

RESULTS

The systematic review identified 15 trials with 6986 patients. The meta-analysis revealed that treatment with probiotic or synbiotic reduced significantly both the duration of diarrhea [Weighted mean difference (WMD) = -1.05 day, 95% CI (-1.98, -0.11)] and the hospital stay duration [Standard mean difference (SMD) = -2.87 days, 95% CI (-5.33, -0.42)], especially in specific patient subsets. In both groups, similar rates of vomiting and nutritional recovery were observed. No probiotics or synbiotics-related adverse effects were reported. Subgroup analyses showed that probiotic and synbiotic treatment were more effective in reducing risk of diarrhea in outpatients [Risk ratio (RR) = 0.86, 95%CI (0.75-0.98)].

CONCLUSION

This meta-analysis supports the potential beneficial roles of probiotics and synbiotics on diarrhea in undernourished children.

Iron Supplementation Influence on the Gut Microbiota and Probiotic Intake Effect in Iron Deficiency-A Literature-Based Review

Iron deficiency in the human body is a global issue with an impact on more than two billion individuals worldwide. The most important functions ensured by adequate amounts of iron in the body are related to transport and storage of oxygen, electron transfer, mediation of oxidation-reduction reactions, synthesis of hormones, the replication of DNA, cell cycle restoration and control, fixation of nitrogen, and antioxidant effects. In the case of iron deficiency, even marginal insufficiencies may impair the proper functionality of the human body. On the other hand, an excess in iron concentration has a major impact on the gut microbiota composition. There are several non-genetic causes that lead to iron deficiencies, and thus, several approaches in their treatment. The most common methods are related to food fortifications and supplements. In this review, following a summary of iron metabolism and its health implications, we analyzed the scientific literature for the influence of iron fortification and supplementation on the gut microbiome and the effect of probiotics, prebiotics, and/or synbiotics in iron absorption and availability for the organism.

Precision Nutrition and the Microbiome Part II: Potential Opportunities and Pathways to Commercialisation

Modulation of the human gut microbiota through probiotics, prebiotics and dietary fibre are recognised strategies to improve health and prevent disease. Yet we are only beginning to understand the impact of these interventions on the gut microbiota and the physiological consequences for the human host, thus forging the way towards evidence-based scientific validation. However, in many studies a percentage of participants can be defined as 'non-responders' and scientists are beginning to unravel what differentiates these from 'responders;' and it is now clear that an individual's baseline microbiota can influence an individual's response. Thus, microbiome composition can potentially serve as a biomarker to predict responsiveness to interventions, diets and dietary components enabling greater opportunities for its use towards disease prevention and health promotion. In Part I of this two-part review, we reviewed the current state of the science in terms of the gut microbiota and the role of diet and dietary components in shaping it and subsequent consequences for human health. In Part II, we examine the efficacy of gut-microbiota modulating therapies at different life stages and their potential to aid in the management of undernutrition and overnutrition. Given the significance of an individual's gut microbiota, we investigate the feasibility of microbiome testing and we discuss guidelines for evaluating the scientific validity of evidence for providing personalised microbiome-based dietary advice. Overall, this review highlights the potential value of the microbiome to prevent disease and maintain or promote health and in doing so, paves the pathway towards commercialisation.

Consumption of Galacto-Oligosaccharides Increases Iron Absorption from Ferrous Fumarate: A Stable Iron Isotope Study in Iron-Depleted Young Women

BACKGROUND

Animal studies suggest prebiotics can increase iron absorption, but results from human studies are equivocal.

OBJECTIVES

In iron-depleted women, before (baseline) and after daily consumption of galacto-oligosaccharides (GOS) for 4 wk, we sought to assess fractional iron absorption (FIA) from an iron supplement given with and without single doses of GOS in test meals or water.

METHODS

In all women (n = 34; median serum ferritin concentration = 16.4 µg/L), FIA from doses of 14 mg iron labeled with stable isotopes was measured in the following conditions at baseline: 1) FIA from ferrous fumarate (FeFum) in water given with and without 15 g GOS; 2) FIA from FeFum in a test meal given with and without 15 g GOS; 3) FIA from ferrous sulfate (FeSO4) in a test meal given without 15 g GOS. All subjects then consumed ∼15 g GOS daily for 4 wk. Then the following conditions were tested: 4) FIA from FeFum in a test meal with and without 15 g GOS; and 5) FIA from FeSO4 in a test meal with 15 g GOS. FIA was measured as erythrocyte incorporation of stable isotopes.

RESULTS

At baseline, GOS significantly increased FIA from FeFum when given with water (+61%; P < 0.001) and the meal (+28%; P = 0.002). After 4 wk of GOS consumption, GOS again significantly increased FIA from FeFum in the meal (+29%; P = 0.044). However, compared with baseline, consumption of GOS for 4 wk did not significantly enhance absorption from FeFum in the meal given without GOS. FIA from FeSO4 given with GOS in a meal after 4 wk of GOS consumption was not significantly greater than FIA from FeSO4 in a meal without GOS at baseline.

CONCLUSIONS

In iron-depleted women, GOS given with FeFum increases FIA, but 4 wk of GOS consumption did not enhance this effect. The study was registered at clinicaltrials.gov as NCT03325270.

Use of a Probiotic to Enhance Iron Absorption in a Randomized Trial of Pediatric Patients Presenting with Iron Deficiency

OBJECTIVE

To evaluate the efficacy of low dose ferrous sulfate for the treatment of iron deficiency and if the probiotic Lactobacillus plantarum 299v (LP299v) enhances treatment.

STUDY DESIGN

This randomized, double-blinded, controlled trial of the treatment of iron deficiency in children compared the use of low-dose ferrous sulfate (1-3 mg/kg/day), with or without probiotic (LP299v).

RESULTS

Serum ferritin level increased in all children from a baseline of 23.7 ng/mL to 45.4 ng/mL after 6-8 weeks of treatment. There was no significant difference in the increase in serum ferritin in children taking the probiotic LP299v compared with controls (23.2 vs 20.0 ng/mL, respectively). Additionally, an increase in ferritin level was not significantly associated with probiotic use when controlling for other factors, including child weight and dosing. Overall, the treatments were well-tolerated, with mild side effects.

CONCLUSIONS

Treatment with low-dose ferrous sulfate is well-tolerated and effective in correcting iron deficiency in children. However, the probiotic LP299v did not enhance treatment. Further attention should examine the dose-response effect in children, including an alternate day dosing schedule.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT01617044.

Lactobacillus rhamnosus GG can protect malnourished children

Malnutrition affects virtually all organ systems, and malnourished children are more prone to infections. These children have dysbiosis, but probiotics can restore the disrupted gut microbiome. We investigated the protective effects of Lactobacillus rhamnosus GG in malnourished children in terms of incidence of infection, and anthropometric and metabolic parameters. 50 intervention and 50 control patients, aged 6 months to 5 years, with body weight and height below -2 SD, were randomly and prospectively recruited. The controls received a calorie and protein-appropriate diet for 3 months, while the study group additionally received approximately 10⁹ L. rhamnosus GG for 3 months. Infection episodes and nutritional status were compared between the groups. 38 intervention, 33 control patients completed the study and the two groups were similar at baseline. The study group had fewer upper respiratory tract infections and gastroenteritis episodes at each month and at the end of the study. Children in the study group experienced fewer total upper respiratory infections and urinary tract infections. Hospitalisation was more frequent in the control group during the third month and at the end of the study. Total infection numbers were higher in the control group at each month and at the end of the study (P<0.001 for each). Increments in body mass index (BMI) and BMI Z-scores were more pronounced in the study group (P=0.008 and P=0.02, respectively). Daily prophylactic use of L. rhamnosus GG at 10⁹ bacteria in malnourished children prevents most infections and improves nutritional status when used together with appropriate diet.

Developmental origins of health and disease: current knowledge and potential mechanisms

Epidemiologic and clinical research has provided a large body of evidence supporting the developmental origins of health and disease (DOHaD), but there has been a relative dearth of mechanistic studies in humans due to the complexity of working with large, longitudinal cohorts. Nonetheless, animal models of undernutrition have provided substantial evidence for the potential epigenetic, metabolic, and endocrine mechanisms behind DOHaD. Furthermore, recent research has explored the interaction between the environment and the gastrointestinal system by investigating how the gut microbial ecology may impact the capacity for nutrient processing and absorption in a manner that may limit growth. This review presents a summary of current research that supports the concept of DOHaD, as well as potential mechanisms and interactions that explain how nutrition in utero and during early childhood influences lifelong health.

In vitro assessment of iron availability from commercial Young Child Formulae supplemented with prebiotics

PURPOSE

Iron is essential for development and growth in young children; unfortunately, iron deficiency (ID) is a significant public health problem in this population. Young Child Formulae (YCF), milk-derived products fortified with iron and ascorbic acid (AA, an enhancer of iron absorption) may be good sources of iron to help prevent ID. Furthermore, some YCF are supplemented with prebiotics, non-digestible carbohydrates suggested to enhance iron bioavailability. The aim of our study was to evaluate iron bioavailability of YCF relative to prebiotic and AA concentrations. We hypothesised that YCF with the highest levels of prebiotics and AA would have the most bioavailable iron.

METHODS

We used the in vitro digestion/Caco-2 cell model to measure iron bioavailability from 4 commercially available YCF with approximately equal amounts of iron, but varying amounts of: AA and the prebiotics fructo- and galacto-oligosaccharides. Caco-2 cell ferritin formation was used as a surrogate marker for iron bioavailability.

RESULTS

The YCF with the highest concentration of prebiotics and AA had the highest iron bioavailability; conversely, the YCF with the lowest concentration of prebiotics and AA had the lowest. After the addition of exogenous prebiotics, so that all tested YCF had equivalent amounts, there was no longer a significant difference between YCF iron bioavailability.

CONCLUSION

Our results suggest that ascorbic acid and prebiotics in YCF improve iron bioavailability. Ensuring that iron is delivered in a bioavailable form would improve the nutritional benefits of YCF in relation to ID/IDA amongst young children; therefore, further exploration of our findings in vivo is warranted.

Gut microbiota alterations and dietary modulation in childhood malnutrition - The role of short chain fatty acids

The gut microbiome affects the health status of the host through different mechanisms and is associated with a wide variety of diseases. Both childhood undernutrition and obesity are linked to alterations in composition and functionality of the gut microbiome. One of the possible mechanisms underlying the interplay between microbiota and host metabolism is through appetite-regulating hormones (including leptin, ghrelin, glucagon-like peptide-1). Short chain fatty acids, the end product of bacterial fermentation of non-digestible carbohydrates, might be able to alter energy harvest and metabolism through enteroendocrine cell signaling, adipogenesis and insulin-like growth factor-1 production. Elucidating these mechanisms may lead to development of new modulation practices of the gut microbiota as a potential prevention and treatment strategy for childhood malnutrition. The present overview will briefly outline the gut microbiota development in the early life, gut microbiota alterations in childhood undernutrition and obesity, and whether this relationship is causal. Further we will discuss possible underlying mechanisms in relation to the gut-brain axis and short chain fatty acids, and the potential of probiotics, prebiotics and synbiotics for modulating the gut microbiota during childhood as a prevention and treatment strategy against undernutrition and obesity.

The intestinal microbiota, energy balance, and malnutrition: emphasis on the role of short-chain fatty acids

Malnutrition refers to both over- and undernutrition and results from a disruption in energy balance. It affects one in three people worldwide and is associated with increased morbidity and mortality. The intestinal microbiota represents a newly identified factor that might contribute to the development of malnutrition, as it harbors traits that complement the human metabolic and endocrine capabilities, thereby influencing energy balance. Areas covered: In the current review, we aim to give a comprehensive overview on the microbiota, its development and its possible influence on energy balance, with emphasis the role of short-chain fatty acids. We also consider microbial characteristics associated with obesity and undernutrition and evaluate microbial manipulating strategies. The PubMed database was searched using the terms: 'gastrointestinal microbiota', 'volatile fatty acids', 'malnutrition', 'undernutrition', 'obesity', 'insulin resistance', 'prebiotics', 'probiotics', 'antibiotics' and 'fecal microbiota transplantation'. Expert commentary: Microbiota make important contributions to the regulation of energy balance, whereas microbial disturbances might predispose to malnutrition. If we manage to manipulate the microbiota to our benefit, it could lead to preventive or therapeutic strategies targeting malnutrition.

Effect of fortified milk on growth and nutritional status in young children: a systematic review and meta-analysis

Objective

Adequate nutrition is critical for optimal growth and development. However, young children may be at risk of nutrient deficiencies when transitioning to weaning foods for a variety of reasons. Supplementation with fortified milk may provide potentially lacking essential nutrients, but effects on growth and nutritional status are yet to be established.

Design

Five databases were searched for randomised controlled trials using fortified milk against control milk in young children. Outcomes were growth, body composition and/or biochemical markers. Pooled differences in means were calculated for continuous outcomes and odds ratios for binary outcomes.

Setting

Randomised controlled trials set in any country.

Subjects

Otherwise healthy children aged 6–47 months.

Results

Fifteen articles met the eligibility criteria. Fortification varied from Fe, Zn, vitamins, essential fatty acids, to pre- and/or probiotics. Frequently reported outcomes were weight, height and Fe status. Studies varied in geographical location, sample size and duration. Fortified milk had minimal effects on weight gain (mean difference=0·17 kg; 95 % CI 0·02, 0·31 kg) compared with control milk. The risk of anaemia was reduced in fortified milk groups (OR=0·32; 95 % CI 0·15, 0·66) compared with control groups. There were no significant effects on height gain, changes in body composition or Hb concentration.

Conclusions

Fortified milk is an effective source of complementary nutrition to supplement children in need when consumed in appropriate amounts in addition to a normal diet. Due to compositional differences, further research on fortified milk is warranted before making global recommendations on benefits for growth and nutritional outcomes in young children.

Effect of long-term antibiotic use on weight in adolescents with acne

OBJECTIVES

Antibiotics increase weight in farm animals and may cause weight gain in humans. We used electronic health records from a large primary care organization to determine the effect of antibiotics on weight and BMI in healthy adolescents with acne.

METHODS

We performed a retrospective cohort study of adolescents with acne prescribed ≥4 weeks of oral antibiotics with weight measurements within 18 months pre-antibiotics and 12 months post-antibiotics. We compared within-individual changes in weight-for-age Z-scores (WAZs) and BMI-for-age Z-scores (BMIZs). We used: (i) paired t-tests to analyse changes between the last pre-antibiotics versus the first post-antibiotic measurements; (ii) piecewise-constant-mixed models to capture changes between mean measurements pre- versus post-antibiotics; (iii) piecewise-linear-mixed models to capture changes in trajectory slopes pre- versus post-antibiotics; and (iv) χ(2) tests to compare proportions of adolescents with ≥0.2 Z-scores WAZ or BMIZ increase or decrease.

RESULTS

Our cohort included 1012 adolescents with WAZs; 542 also had BMIZs. WAZs decreased post-antibiotics in all analyses [change between last WAZ pre-antibiotics versus first WAZ post-antibiotics = -0.041 Z-scores (P < 0.001); change between mean WAZ pre- versus post-antibiotics = -0.050 Z-scores (P < 0.001); change in WAZ trajectory slopes pre- versus post-antibiotics = -0.025 Z-scores/6 months (P = 0.002)]. More adolescents had a WAZ decrease post-antibiotics ≥0.2 Z-scores than an increase (26% versus 18%; P < 0.001). Trends were similar, though not statistically significant, for BMIZ changes.

CONCLUSIONS

Contrary to original expectations, long-term antibiotic use in healthy adolescents with acne was not associated with weight gain. This finding, which was consistent across all analyses, does not support a weight-promoting effect of antibiotics in adolescents.

Microbiota manipulation for weight change

Manipulation of the intestinal microbiota has been linked to weight changes and obesity. To explore the influence of specific agents that alter the intestinal flora on weight in different patient groups we conducted a meta-analysis of randomized controlled trials (RCTs) reporting on the effects of probiotics, prebiotics, synbiotics, and antibiotics on weight. We searched the Pubmed and Cochrane Library databases for trials on adults, children, and infants evaluating the effects of these substances on weight. Our primary outcome was weight change from baseline. Standardized mean differences (SMDs) with 95% confidence intervals were calculated. We identified and included 13 adult, 17 children, and 23 infant RCTs. Effects were opposite among adults and children, showing weight loss among adults (SMD -0.54 [-0.83, -0.25)) and minor weight gains among children (SMD 0.20 [0.04, 0.36]) and infants (SMD 0.30 [-0.01, 0.62]) taking mainly Lactobacillus probiotic supplements. Heterogeneity was substantial in the adult and infant analyses and could not be explained by intervention or patient characteristics. Azithromycin administration in children with pulmonary disease was associated with weight gain (SMD 0.39 [0.24, 0.54]), without heterogeneity. A high risk of selective reporting and attrition bias was detected across the studies, making it difficult to draw firm conclusions. Overall, our meta-analysis suggests that there may be a role for probiotics in promoting weight loss in adults and weight gain in children, however additional studies are needed. Though we cannot recommend antibiotic administration for weight manipulation, its use provides advantageous weight gain in children with cystic fibrosis and bronchiectasis.

Probiotic strain Lactobacillus plantarum 299v increases iron absorption from an iron-supplemented fruit drink: a double-isotope cross-over single-blind study in women of reproductive age

Iron deficiency is common, especially among young women. Adding probiotics to foods could be one way to increase iron absorption. The aim of this study was to test the hypothesis that non-haem iron absorption from a fruit drink is improved by adding Lactobacillus plantarum 299v (Lp299v). Iron absorption was studied in healthy women of reproductive age using a single-blind cross-over design in two trials applying the double-isotope (⁵⁵Fe and ⁵⁹Fe) technique. In Trial 1, iron absorption from a fruit drink containing 10⁹ colony-forming units (CFU) Lp299v was compared with that from a control drink without Lp299v. Trial 2 had the same design but 10¹⁰ CFU were used. The test and control drinks contained approximately 5 mg of iron as ferrous lactate and were labelled with ⁵⁹Fe (B) and ⁵⁵Fe (A), respectively, and consumed on 4 consecutive days in the order AABB. Retention of the isotopes was measured with whole-body counting and in blood. Mean iron absorption from the drink containing 10⁹ CFU Lp299v (28·6(sd 12·5) %) was significantly higher than from the control drink (18·5(sd 5·8) %), n 10, P<0·028). The fruit drink with 10¹⁰ CFU Lp299v gave a mean iron absorption of 29·1(sd 17·0) %, whereas the control drink gave an absorption of (20·1(sd 6·4) %) (n 11, P<0·080). The difference in iron absorption between the 10⁹ CFU Lp299v and the 10¹⁰ CFU Lp299v drinks was not significant (P=0·941). In conclusion, intake of probiotics can increase iron absorption by approximately 50 % from a fruit drink having an already relatively high iron bioavailability.

Effects of probiotics on child growth: a systematic review

BACKGROUND

Child undernutrition has short and long term consequence for both individuals and society. Previous studies show probiotics may promote child growth and have an impact on under-nutrition.

METHODS

A systematic review of the literature was carried out on three electronic databases to assess evidence. The outcome measured was change in weight or height. A narrative analysis was conducted due to heterogeneity of included studies.

RESULTS

Twelve studies were included in the review of which ten were randomised controlled trials. A total of 2757 children were included, with 1598 from developing countries. The studies varied in type and quantity of probiotics given, duration of interventions, characteristics of participants, setting and units of outcome measures. Overall, five studies found a positive effect of probiotics on child growth. All five were conducted in developing countries with four studies conducted in mostly under-nourished children and one in well-nourished children. No significant effect on growth was found in the seven studies that were conducted in developed countries.

CONCLUSION

The limited evidence suggests that probiotics have the potential to improve child growth in developing countries and in under-nourished children. More research is needed to explore this further.

Structural differences of prebiotic oligosaccharides influence their capability to enhance iron absorption in deficient rats

This study evaluates the influence of novel galacto-oligosaccharides derived from lactulose (GOS-Lu), kojibiose or 4'-galactosyl-kojibiose in hematological parameters of Fe homeostasis using Fe-deficient animals. Liver TfR-2, IL-6, NFκB and PPAR-γ expression (mRNA) were also determined by RT-qPCR analyses, and active hepcidin peptide production and short chain fatty acids by LC coupled to MS/MS or UV detection. Feeding animals with GOS-Lu or kojibiose together with FeCl3 increased hemoglobin (Hb) production (by 17%) and mean Hb concentration into erythrocytes relative to animals administered with FeCl3 alone (14.1% and 19.7%, respectively). Animals administered with prebiotics showed decreased plasmatic hepcidin levels, contributing to a higher intestinal absorption of the micronutrient. These data indicate that concurrent administration of these potentially prebiotic oligosaccharides together with a supplement of Fe ameliorates inflammation-mediated perturbations in the liver, according to the particular structure of the prebiotic compound, and result an attractive strategy to improve Fe absorption.

The stunting syndrome in developing countries

Linear growth failure is the most common form of undernutrition globally. With an estimated 165 million children below 5 years of age affected, stunting has been identified as a major public health priority, and there are ambitious targets to reduce the prevalence of stunting by 40% between 2010 and 2025. We view this condition as a 'stunting syndrome' in which multiple pathological changes marked by linear growth retardation in early life are associated with increased morbidity and mortality, reduced physical, neurodevelopmental and economic capacity and an elevated risk of metabolic disease into adulthood. Stunting is a cyclical process because women who were themselves stunted in childhood tend to have stunted offspring, creating an intergenerational cycle of poverty and reduced human capital that is difficult to break. In this review, the mechanisms underlying linear growth failure at different ages are described, the short-, medium- and long-term consequences of stunting are discussed, and the evidence for windows of opportunity during the life cycle to target interventions at the stunting syndrome are evaluated.

Can prebiotics and probiotics improve therapeutic outcomes for undernourished individuals?

It has become clear in recent years that the human intestinal microbiota plays an important role in maintaining health and thus is an attractive target for clinical interventions. Scientists and clinicians have become increasingly interested in assessing the ability of probiotics and prebiotics to enhance the nutritional status of malnourished children, pregnant women, the elderly, and individuals with non-communicable disease-associated malnutrition. A workshop was held by the International Scientific Association for Probiotics and Prebiotics (ISAPP), drawing on the knowledge of experts from industry, medicine, and academia, with the objective to assess the status of our understanding of the link between the microbiome and under-nutrition, specifically in relation to probiotic and prebiotic treatments for under-nourished individuals. These discussions led to four recommendations:   (1) The categories of malnourished individuals need to be differentiated To improve treatment outcomes, subjects should first be categorized based on the cause of malnutrition, additional health-concerns, differences in the gut microbiota, and sociological considerations. (2) Define a baseline "healthy" gut microbiota for each category Altered nutrient requirement (for example, in pregnancy and old age) and individual variation may change what constitutes a healthy gut microbiota for the individual. (3) Perform studies using model systems to test the effectiveness of potential probiotics and prebiotics against these specific categories These should illustrate how certain microbiota profiles can be altered, as members of different categories may respond differently to the same treatment. (4) Perform robust well-designed human studies with probiotics and/or prebiotics, with appropriate, defined primary outcomes and sample size These are critical to show efficacy and understand responder and non-responder outcomes. It is hoped that these recommendations will lead to new approaches that combat malnutrition. This report is the result of discussion during an expert workshop titled "How do the microbiota and probiotics and/or prebiotics influence poor nutritional status?" held during the 10th Meeting of the International Scientific Association for Probiotics and Prebiotics (ISAPP) in Cork, Ireland from October 1-3, 2012. The complete list of workshop attendees is shown in Table 1.

Effect of a Growing-up Milk Containing Synbiotics on Immune Function and Growth in Children: A Cluster Randomized, Multicenter, Double-blind, Placebo Controlled Study

Common infectious diseases, such as diarrhea, are still the major cause of death in children under 5-years-old, particularly in developing countries. It is known that there is a close relationship between nutrition and immune function. To evaluate the effect of a growing-up milk containing synbiotics on immune function and child growth, we conducted a cluster randomized, multicenter, double-blind, placebo controlled clinical trial in children between 18 and 36 months of age in Vietnam. Eligible children from eight and seven kindergartens were randomly assigned to receive test and isocaloric/ isoproteic control milk, respectively, for 5 months. We found that the blood immunoglobulin A (IgA) level and growth parameters were increased in the test group. Compared to the control group, there was also a trend of decreased vitamin A deficiency and fewer adverse events in the test group. These data suggest that a growing-up milk containing synbiotics may be useful in supporting immune function and promoting growth in children.

Probiotics Lactobacillus reuteri DSM 17938 and Lactobacillus casei CRL 431 modestly increase growth, but not iron and zinc status, among Indonesian children aged 1-6 years

Probiotics and milk calcium may increase resistance to intestinal infection, but their effect on growth and iron and zinc status of Indonesian children is uncertain. We investigated the hypotheses that cow milk with added probiotics would improve growth and iron and zinc status of Indonesian children, whereas milk calcium alone would improve growth but reduce iron and zinc status. A 6-mo randomized trial was conducted in low-socioeconomic urban communities of Jakarta. Healthy children (n = 494) were randomly assigned to receive low-lactose milk with a low calcium content of ∼50 mg/d (LC; n = 124), a regular calcium content of ∼440 mg/d (RC group; n = 126), regular calcium with 5 × 10(8) CFU/d Lactobacillus casei CRL 431 (casei; n = 120), or regular calcium with 5 × 10(8) CFU/d Lactobacillus reuteri DSM 17938 (reuteri; n = 124). Growth, anemia, and iron and zinc status were assessed before and after the intervention. Compared with the RC group, the reuteri group had significantly greater weight gain [0.22 (95% CI: 0.02, 0.42) kg], weight-for-age Z-score (WAZ) changes [0.09 (95% CI: 0.01, 0.17)], and monthly weight [0.03 (95% CI: 0.002, 0.05) kg/mo] and height [0.03 (95% CI: 0.01, 0.05) cm/mo] velocities. Casei significantly increased monthly weight velocity [0.03 (95% CI: 0.001, 0.05) kg/mo], but not height. However, the changes in underweight, stunting, anemia prevalence, and iron and zinc status were similar between groups. In conclusion, L. reuteri DSM 17938 modestly improved growth by increasing weight gain, WAZ changes, and weight and height velocity, whereas L. casei CRL 431 modestly improved weight velocity. Independent from probiotics supplementation, regular milk calcium did not affect growth or iron and zinc status.

Inulin modifies the bifidobacteria population, fecal lactate concentration, and fecal pH but does not influence iron absorption in women with low iron status

BACKGROUND

Bioavailability of nonheme iron is influenced by the concentration of inhibitors and enhancers in the diet. The fructans inulin and oligofructose have been shown to improve iron absorption in animals through colonic uptake, but this has not been confirmed in humans.

OBJECTIVE

The aim of the intervention study was to evaluate the influence of inulin on iron absorption, bifidobacteria, total bacteria, short-chain fatty acids (SCFAs), and fecal pH in women with low iron status (plasma ferritin <25 μg/L).

DESIGN

The subjects (n = 32) consumed inulin or placebo 3 times/d (∼20 g/d) for 4 wk, separated by a 2-wk washout period. Iron absorption was measured after 3 wk of inulin and placebo consumption from a standard test meal by using stable-iron-isotope techniques. Fecal bacteria were measured by quantitative polymerase chain reaction, and fecal acids by HPLC.

RESULTS

Mean fractional iron absorption in the inulin (15.2%; 95% CI: 8.0%, 28.9%) and placebo (13.3%; 95% CI: 8.1%, 24.3%) periods did not differ significantly (P = 0.10). Inulin decreased fecal pH (P < 0.001) and increased fecal bifidobacteria (P < 0.001) and fecal lactate (P < 0.001) but had no effect on fecal SCFAs and total bacteria. Changes in lactate and acetate concentrations were positively correlated with changes in propionate (P < 0.001) and butyrate (P < 0.02) concentrations, respectively. Iron absorption correlated with fecal pH in the placebo period (P < 0.01) but not in the inulin period (P = 0.37).

CONCLUSION

Although inulin showed prebiotic activity, we were unable to show an increase in iron absorption in women with low iron status. This trial was registered at clinicaltrials.gov as NCT0148309.

Early life: gut microbiota and immune development in infancy

The immune system of infants is actively downregulated during pregnancy and therefore the first months of life represent a period of heightened susceptibility to infection. After birth, there is an age-dependent maturation of the immune system. Exposure to environmental microbial components is suggested to play an important role in the maturation process. The gastrointestinal tract is the major site of interaction between the host immune system and microorganisms, both commensal as well as potentially pathogenic. It is well established that the mammalian immune system is designed to help protect the host from invading microorganisms and other danger signals. However, recent research is emerging in the field of host-microbe interactions showing that commensal microorganisms (microbiota) are most likely one of the drivers of immune development and, in turn the immune system shapes the composition of the microbiota. Specific early microbial exposure of the gut is thought to dramatically reduce the incidence of inflammatory, autoimmune and atopic diseases further fuelling the scientific view that microbial colonisation plays an important role in regulating and fine-tuning the immune system throughout life. Therefore, the use of pre-, pro- and synbiotics may result in a beneficial microbiota composition that might have a pivotal role on the prevention of several important diseases that develop in early life such as necrotizing enterocolitis and atopic eczema.