Safety and efficacy of adding postbiotics in infant formula: a systematic review and meta-analysis

Effect of Pro-, Pre- and Synbiotic Supplementation on the Growth of Infants and Children: An Umbrella Systematic Review and Meta-Analysis

BACKGROUND

In recent years, pro-, pre- and synbiotics have been suggested to positively influence the growth outcomes of infants and children. However, the findings have been inconsistent. This umbrella meta-analysis was conducted to evaluate this effect.

METHODS

The PubMed, Web of Science and Scopus databases were systematically searched until June 2024 to identify relevant studies. Weight gain, length gain, head circumstance (HC) gain, body mass index (BMI) as well as weight-for-height (WHZ), height-for-age (HAZ), weight-for-age (WAZ) and BMI-for-age (BMIAZ) Z-scores were considered as the outcomes. Standardised mean differences (SMD) along with the 95% confidence interval (CI) were utilised to estimate the overall effect size. Subgroup analyses were conducted to identify the sources of heterogeneity among the studies.

RESULTS

We included 26 meta-analyses, which encompassed a total of 72 285 participants. The pooled umbrella analysis revealed positive effects of pro-, pre- and synbiotics on weight gain (SMD = 0.17, 95% CI: 0.09-0.25) and height gain (SMD = 0.10, 95% CI: 0.01-0.19) in both healthy individuals and preterm infants, although significant heterogeneity was observed across the studies (p < 0.001). Furthermore, the subgroup analyses indicated very weak evidence for an increase in BMI and WAZ following microbiome-based interventions.

CONCLUSION

Supplementation with pro-, pre- and synbiotics has the potential to enhance weight and height gain in infants and children. Additional large-scale studies are needed to confirm their clinical applications.

A Comprehensive Review on Dietary Polysaccharides as Prebiotics, Synbiotics, and Postbiotics in Infant Formula and Their Influences on Gut Microbiota

Human milk contains an abundance of nutrients which benefit the development and growth of infants. However, infant formula has to be used when breastfeeding is not possible. The large differences between human milk and infant formula in prebiotics lead to the suboptimal intestinal health of infant formula-fed infants. This functional deficit of infant formula may be overcome through other dietary polysaccharides that have been characterized. The aim of this review was to summarize the potential applications of dietary polysaccharides as prebiotics, synbiotics, and postbiotics in infant formula to better mimic the functionality of human milk prebiotics for infant gut health. Previous studies have demonstrated the influences of dietary polysaccharides on gut microbiota, SCFA production, and immune system development. Compared to prebiotics, synbiotics and postbiotics showed better application potential in shaping the gut microbiota, the prevention of pathogen infections, and the development of the immune system. Moreover, the safety issues for biotics still require more clinical trials with a large-scale population and long time duration, and the generally accepted regulations are important to regulate related products. Pectin polysaccharides has similar impacts to human milk oligosaccharides on gut microbiota and the repairing of a damaged gut barrier, with similar functions also being observed for inulin and β-glucan. Prebiotics as an encapsulation material combined with probiotics and postbiotics showed better potential applications compared to traditional material in infant formula.

Probiotic, Postbiotic, and Paraprobiotic Effects of Lactobacillus rhamnosus as a Modulator of Obesity-Associated Factors

Obesity is a pandemic currently affecting the world's population that decreases the quality of life and promotes the development of chronic non-communicable diseases. Lactobacillus rhamnosus is recognized for multiple positive effects on obesity and overall health. In fact, such effects may occur even when the microorganisms do not remain alive (paraprobiotic effects). This raises the need to elucidate the mechanisms by which obesity-associated factors can be modulated. This narrative review explores recent findings on the effects of L. rhamnosus, particularly, its postbiotic and paraprobiotic effects, on the modulation of adiposity, weight gain, oxidative stress, inflammation, adipokines, satiety, and maintenance of intestinal integrity, with the aim of providing a better understanding of its mechanisms of action in order to contribute to streamlining its clinical and therapeutic applications. The literature shows that L. rhamnosus can modulate obesity-associated factors when analyzed in vitro and in vivo. Moreover, its postbiotic and paraprobiotic effects may be comparable to the more studied probiotic actions. Some mechanisms involve regulation of gene expression, intracellular signaling, and enteroendocrine communication, among others. We conclude that the evidence is promising, although there are still multiple knowledge gaps that require further study in order to fully utilize L. rhamnosus to improve human health.

Postbiotics are a candidate for new functional foods

Accumulating studies have highlighted the great potential of postbiotics in alleviating diseases and protecting host health. Compared with traditional functional foods (such as probiotics and prebiotics), postbiotics have the advantages of a single composition, high physiological activity, long shelf life, easy absorption, and high targeting, etc. The development of postbiotics has led to a wide range of potential applications in functional food and drug development. However, the lack of clinical trial data, mechanism analyses, safety evaluations, and effective regulatory frameworks has limited the application of postbiotic products. This review describes the definition, classification, sources, and preparation methods of postbiotics, the progress and mechanism of preclinical and clinical research in improving host diseases, and their application in food. Strengthen understanding of the recognition and development of related products to lay a theoretical foundation.

An update on the use of 'biotics' in pediatric infectious gastroenteritis

INTRODUCTION

Acute gastroenteritis (AGE) is the consequence of a disturbed gastro-intestinal microbiome. Certain probiotic strains (Lacticaseibacillus rhamnosus, Saccharomyces boulardii CNCM I-745, Limosilactobacillus reuteri (L. reuteri) DSM 17,938, the combination of L. rhamnosus 19070-2 and L. reuteri DSM 12,246) reduce the duration and severity of diarrhea.

AREAS COVERED

Relevant literature was sourced from PubMed and CINAHL. Important reviews until 2021 were summarized in tables. New evidence for pro-, pre-, syn- and postbiotics in AGE was searched for. Postbiotics offer advantages regarding product stability and show accumulating evidence. Heterogeneity in studies regarding the in- and exclusion criteria, primary and secondary endpoints, type, dose, timing and duration of biotic administration limits the evidence.

EXPERT OPINION

Development of a core outcome set for children with AGE would be beneficial, as its application would increase the homogeneity of the available evidence. The vast majority of the 'biotics' is registered as food supplement. Regulations for food supplements prioritize safety over efficacy, making them considerably more tolerant compared to the regulation for registration as medication. We recommend that at least one randomized controlled trial is published with the commercialized product before marketing the product, despite the fact that legislation regarding food supplements requires only safety data.