Effects of synbiotic supplementation on anthropometric indices and body composition in overweight or obese children and adolescents: a randomized, double-blind, placebo-controlled clinical trial

The Role of Gut Microbiota in Pediatric Obesity and Metabolic Disorders: Insights from a Comprehensive Review

Background: Pediatric obesity represents a multifactorial condition in which gut microbiota dysbiosis, low-grade systemic inflammation, and metabolic dysfunction are intricately connected. Objectives: This systematic review sought to evaluate and integrate current findings regarding the interactions between gut microbial composition, dietary influences, inflammatory status, and metabolic outcomes in obese pediatric populations. Methods: A comprehensive search of PubMed, Scopus, and Web of Science databases was conducted for studies published from January 2010 onward. Eligible studies comprised randomized controlled trials, and cohort, cross-sectional, and longitudinal designs involving individuals aged ≤18 years. Study quality was appraised using the NIH Study Quality Assessment Tool. Results: Sixteen studies fulfilled the inclusion criteria. Dysbiosis was consistently observed among obese children, characterized by alterations in microbial diversity and abundance associated with increased inflammation and adverse metabolic profiles. Dietary interventions, notably symbiotic supplementation and adherence to Mediterranean diet patterns, were associated with favorable modulation of gut microbiota and inflammatory parameters. The majority of studies demonstrated high methodological quality, although minor observational limitations were noted. Conclusions: Gut microbiota dysregulation plays a central role in the development of metabolic and inflammatory complications associated with pediatric obesity. Although dietary and microbiota-modifying strategies show therapeutic promise, their effectiveness must be substantiated through robust, long-term studies.

The Role of Nutraceuticals and Probiotics in Addition to Lifestyle Intervention in the Management of Childhood Obesity-Part 1: Metabolic Changes

Childhood obesity is a growing global health issue. Its rising prevalence is linked to genetic, environmental, and lifestyle factors. Obesity in children could lead to different comorbidities and complications with an increased risk of metabolic disorders, such as insulin resistance, dyslipidemia, type 2 diabetes mellitus (T2DM), and metabolic dysfunction-associated steatotic liver disease (MASLD). First-line treatment involves dietary modifications and lifestyle changes; however, adherence is often poor and remains a significant challenge. Pharmacotherapy, while a potential option, has limitations in availability and can cause side effects, leading to growing interest in alternative treatments, such as nutraceutical compounds. Derived from natural sources, these compounds have different anti-inflammatory, antiallergic, antioxidant, antibacterial, antifungal, neuroprotective, antiaging, antitumor, insulin-sensitizing, glucose, and lipid-lowering effects. This review describes commonly used nutraceutical compounds, such as omega-3 fatty acids, vitamin D, polyphenols (such as resveratrol and curcumin), berberine, white mulberry leaves and others, and pre- and probiotics in the management of obesity, evaluating the evidence on their mechanisms of action and efficacy in metabolic comorbidities. The evidence suggests that the integration of nutraceuticals into the diet may positively influence body mass index, glucose metabolism, lipid profiles, and gut microbiota composition and reduce inflammation in obese individuals. These effects may provide future practical guidance for clinical practice, contribute to metabolic health improvement, and potentially prevent obesity-related complications. In this first part, we discuss the effects of nutraceutical compounds on insulin sensitivity and insulin resistance, T2DM, dyslipidemia, and MASLD in addition to diet and lifestyle interventions.

Effect of Bacillus coagulans BC99 supplementation on body weight and gut microbiota in overweight and obese individual: a randomized, double-blind, placebo-controlled study

Introduction

Probiotic supplementation is a safe and effective way to reduce overweight and obesity by regulating the gut microbiota. The Bacillus coagulans strain BC99 is derived from humans and has various probiotic-related, acid resistance, bile salt resistance, and adhesion-related domains in the genome. This study aimed to assess the effects of BC99 on the gut microbiota, body weight and lipid profiles of overweight and obese individuals.

Methods

A total of 66 adult individuals were randomly assigned to a probiotic group (supplemented with 5 × 109 colony-forming units of BC99 per day along with 3 g of maltodextrin) and placebo group (supplemented with 3 g of maltodextrin daily) in a 1:1 ratio.

Results

After 8 weeks of oral administration, BC99 intervention significantly decreased the body weight of overweight individual (P < 0.01). Weight loss was significantly greater in the probiotic group than in the placebo group (P < 0.05). No significant differences were observed in lipid profiles between two groups. The microbiota analysis revealed that BC99 intervention significantly improved the β-diversity at week 4. The genus Parabacteroides was negatively correlated with body weight and was found to be enriched in the BC99 group.

Discussion

These findings suggest that B. coagulans strain BC99 could be a beneficial candidate for modulating the gut microbiota and improve body weight management for overweight individuals.

Clinical trial registration

ClinicalTrials.gov, identifier NCT06077383.

Small Intestinal Bacterial Overgrowth and Pediatric Obesity-A Systematic Review

Background/Objectives: Childhood obesity is a growing global concern linked to metabolic disorders such as nonalcoholic fatty liver disease (NAFLD). Small intestinal bacterial overgrowth (SIBO) may exacerbate these conditions by promoting systemic inflammation and metabolic dysfunction. This review evaluates the prevalence of SIBO in obese children, its association with inflammatory and metabolic markers, and the efficacy of diagnostic and therapeutic strategies. Methods: A systematic search of PubMed, Scopus, and Web of Science (2010-present) was conducted using Boolean operators: ('small intestinal bacterial overgrowth' OR 'SIBO') AND 'prevalence' AND ('low-grade inflammatory markers' OR 'metabolic status') AND 'gut microbiome' AND 'dysbiosis' AND 'obese children'. Results: The data show that SIBO is frequently observed in obese pediatric populations and is associated with gut dysbiosis, impaired nutrient absorption, and reduced production of short-chain fatty acids. These changes contribute to increased intestinal permeability, endotoxemia, and chronic low-grade inflammation. Several microbial taxa have been proposed as biomarkers and therapeutic targets. Diagnostic inconsistencies persist, but treatments such as probiotics, prebiotics, dietary interventions, and selective antibiotics show potential, pending further validation. Conclusions: Early identification and treatment of SIBO with tailored strategies may help reduce metabolic complications and improve outcomes in children with obesity.

Effect of the consumption of cashew nut (Anacardium occidentale l.) flour-based biscuits in overweight children: a pilot randomized clinical trial

Introduction

Background: cashew nut is an almond known for its cardiovascular benefits in adults and weight gain effects in malnourished children, as supported by research. However, its impact on overweight children remains unexplored. Objective: to analyze the effect of consuming biscuits made with cashew nut flour on the blood glucose and serum triglyceride levels of children with overweight/obesity over four weeks. Methods: a pilot, randomized, open-label clinical study was conducted with 19 overweight children (11 in intervention group 1 [G1] and 8 in group 2 [G2], aged between 7 and 15 years. Over four consecutive weeks, they consumed, daily, three biscuits with 50 % cashew nut flour composition (G1) and six biscuits with 50 % cashew nut flour composition (G2). The biomarkers analyzed were glycated hemoglobin (HbA1c), triglycerides (TG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and total cholesterol (TC) at baseline and seven days post-biscuit consumption. Results: post-experiment, the TG (p = 0.153), HDL-C (p = 0.895), and TC (p = 0.122) biomarkers showed no significant changes. LDL-C levels experienced a slight but statistically significant increase of 0.52 % across all participants (p = 0.031). In contrast, non-HDL cholesterol levels saw a minor yet significant reduction of -1.7 % in serum concentration (p = 0.014). Independent of group allocation, the participants' HbA1c and average blood glucose levels significantly decreased by 12.1 % (p < 0.001) and 17.9 % (p < 0.001), respectively (Cohen's Δ = 1, in both instances). Conclusion: consumption of biscuits containing cashew nut flour by overweight/obese children positively affected the reduction of blood glucose and non-HDL cholesterol biomarkers in both groups, regardless of the formulations used.

Interventions for Childhood Central Obesity: A Systematic Review and Meta-Analysis

Importance

The rapid rise in childhood central obesity and its cardiometabolic complications in adulthood highlight the urgent need for targeted global interventions.

Objective

To examine the association of lifestyle, behavioral, and pharmacological interventions with childhood central obesity.

Data Sources

MEDLINE, Embase, CINHAL, PsycINFO, PubMed, Academic Search Database, and ProQuest from inception to September 25, 2024.

Study Selection

Inclusion criteria included (1) randomized clinical trials (RCTs) focusing on children aged 5 to 18 years with overweight or obesity at baseline and (2) measured central obesity as a primary or secondary outcome.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses reporting guideline was followed. Two authors independently extracted data. Risk of bias was assessed using the revised Cochrane risk-of-bias tool (RoB 2.0). A random-effects meta-analysis was conducted to pool standardized mean differences (SMD) from individual studies. Sensitivity analysis, meta-regression, and subgroup analyses were also conducted.

Main Outcomes and Measures

The main outcome was childhood central obesity measured using waist circumference (WC), waist-to-height ratio, waist-to-hip ratio, and WC z score.

Results

This review included 34 RCTs, involving 8183 children aged 5 to 18 years. Twelve studies had a low risk of bias, whereas 8 were deemed to have a higher risk of bias. The meta-analysis of 2 RCTs examining low-fat lunchboxes and a Mediterranean diet along with physical activity (lasting up to 150 minutes per week over 6 to 9 months) showed a significant association with WC (standard mean difference [SMD], -0.38 [95% CI, -0.58 to -0.19]). Five additional RCTs involved behavioral interventions on dietary education to reduce unhealthy snacks, increase fruit and vegetable intake, promote daily physical activity, and limit screen time, supported by online resources also showed a significant association with WC (SMD, -0.54 [95% CI, -1.06 to -0.03]). However, standalone dietary, physical activity, pharmacotherapy, dietary supplements, motivational interviewing, and combined dietary, physical activity, and behavioral methods did not show a significant association with WC.

Conclusions and Relevance

In this meta-analysis of RCTs, combining dietary changes with physical activity, as well as using behavioral strategies alone, were associated with reduced central obesity in children from high- and middle-income countries. Findings from this study have policy implications for Sustainable Development Goals of ending all forms of malnutrition and reducing premature mortality from noncommunicable diseases.

The Functions of Major Gut Microbiota in Obesity and Type 2 Diabetes

Background: Gut microbiomes play a vital role in maintaining whole-body metabolic homeostasis. It has gained significant attention in recent years due to advancements in genome sequencing technologies and a deeper understanding of its relationship with obesity. However, the specific ways in which different microorganisms directly or indirectly influence host obesity, as well as the underlying mechanisms, remain uncertain because of the complexity of gut microbiota composition. Methods: In this review, we summarize the roles of the major gut microbiota phyla such as Bacteroidetes, Firmicutes, Proteobacteria, and Verrucomicrobia in obesity and type 2 diabetes based on studies published in the past five years on PubMed and Google Scholar. The current therapeutic strategies associated with gut microbiota are also explored from clinical trials, and challenges and future directions are discussed. Results and Conclusions: This review will provide a deeper understanding of the functions of major gut microbiota in obesity and type 2 diabetes, which could lead to more individualized and effective treatments for metabolic diseases.

The Impact of Bioactive Molecules from Probiotics on Child Health: A Comprehensive Review

Background: This review investigates the impact of bioactive molecules produced by probiotics on child health, focusing on their roles in modulating gut microbiota, enhancing immune function, and supporting overall development. Key metabolites, including short-chain fatty acids (SCFAs), bacteriocins, exopolysaccharides (EPSs), vitamins, and gamma-aminobutyric acid (GABA), are highlighted for their ability to maintain gut health, regulate inflammation, and support neurodevelopment. Objectives: The aim of this review is to examine the mechanisms of action and clinical evidence supporting the use of probiotics and postbiotics in pediatric healthcare, with a focus on promoting optimal growth, development, and overall health in children. Methods: The review synthesizes findings from clinical studies that investigate the effects of probiotics and their metabolites on pediatric health. The focus is on specific probiotics and their ability to influence gut health, immune responses, and developmental outcomes. Results: Clinical studies demonstrate that specific probiotics and their metabolites can reduce gastrointestinal disorders, enhance immune responses, and decrease the incidence of allergies and respiratory infections in pediatric populations. Additionally, postbiotics-bioactive compounds from probiotic fermentation-offer promising benefits, such as improved gut barrier function, reduced inflammation, and enhanced nutrient absorption, while presenting fewer safety concerns compared to live probiotics. Conclusions: By examining the mechanisms of action and clinical evidence, this review underscores the potential of integrating probiotics and postbiotics into pediatric healthcare strategies to promote optimal growth, development, and overall health in children.

Effects of probiotics, prebiotics, and synbiotics on cardiometabolic risk factors in children and adolescents with overweight or obesity: a systematic review and Bayesian network meta-analysis

The efficacy of probiotics, prebiotics, or synbiotics in children and adolescents with overweight or obesity remains uncertain. This systematic review evaluates their intervention effects through a network meta-analysis of randomized clinical trials (RCTs). Searches of 4 electronic databases until January 7, 2024, yielded 17 papers reporting on 15 RCTs involving 820 participants. Multiple-strain probiotics (MSP) showed significant efficacy in reducing BMI (Mean Difference (MD) -2.13 kg/m2, 95% credible interval (CrI) [-2.7, -1.57]), waist circumference (MD -1.34 cm, 95% CrI [-2.33, -0.35]), total cholesterol (MD -6.55 mg/dL, 95% CrI [-10.61, -2.45]), triglycerides (MD -3.71 mg/dL, 95% CrI [-5.76, -1.67]), leptin (MD -3.99 ng/mL, 95% CrI [-4.68, -3.3]), and hypersensitive C-reactive protein (Hs-CRP) (MD -1.21 mg/L, 95% CrI [-1.45, -0.97]). Synbiotics were effective in reducing BMI-z score (MD -0.07, 95% CrI [-0.10, -0.04]) and LDL-C (MD -1.54 mg/dL, 95% CrI [-1.98, -1.09]) but led to a slight increase in fasting glucose (MD 1.12 mg/dL, 95% CrI [0.75, 1.49]). Single-ingredient prebiotics and single-strain probiotics also had some beneficial effects on BMI and Hs-CRP, respectively. Moderate to low evidence suggests MSP may be a potential choice for improving BMI and reducing lipids, leptin, and Hs-CRP levels, implying that MSP could aid in managing pediatric obesity and related metabolic issues by modulating the gut microbiota. Although synbiotics show their favorable effects on body metrics and lipid control, their potential impact on blood glucose currently prevents them from being an alternative to MSP for treating pediatric obesity. Further large-scale, well-designed studies are needed to confirm these findings.

Insights into Gut Dysbiosis: Inflammatory Diseases, Obesity, and Restoration Approaches

The gut microbiota is one of the most critical factors in human health. It involves numerous physiological processes impacting host health, mainly via immune system modulation. A balanced microbiome contributes to the gut's barrier function, preventing the invasion of pathogens and maintaining the integrity of the gut lining. Dysbiosis, or an imbalance in the gut microbiome's composition and function, disrupts essential processes and contributes to various diseases. This narrative review summarizes key findings related to the gut microbiota in modern multifactorial inflammatory conditions such as ulcerative colitis or Crohn's disease. It addresses the challenges posed by antibiotic-driven dysbiosis, particularly in the context of C. difficile infections, and the development of novel therapies like fecal microbiota transplantation and biotherapeutic drugs to combat these infections. An emphasis is given to restoration of the healthy gut microbiome through dietary interventions, probiotics, prebiotics, and novel approaches for managing gut-related diseases.

A comprehensive review of synbiotics: an emerging paradigm in health promotion and disease management

Synbiotics are complex preparations of prebiotics that can be selectively utilized by live microorganisms to improve host health. Synbiotics are divided into complementary synbiotics, which consist of probiotics and prebiotics with independent functions, and synergistic synbiotics, which consist of prebiotics that are selectively used by gut microorganisms. Complementary synbiotics used in human clinical trials include Lactobacillus spp. and Bifidobacterium spp. as probiotics, and fructooligosaccharides, galactooligosaccharides, and inulin as prebiotics. Over the past five years, synbiotics have been most commonly used in patients with metabolic disorders, including obesity, and immune and gastrointestinal disorders. Several studies have observed alterations in the microbial community; however, these changes did not lead to significant improvements in disease outcomes or biochemical and hematological markers. The same synbiotics have been applied to individuals with different gut environments. As a result, even with the same synbiotics, there are non-responders who do not respond to the applied synbiotics due to the different intestinal environment for each individual. Therefore, to obtain meaningful results, applying different synbiotics depending on the individual is necessary. Synergistic synbiotics are one solution to circumvent this problem, as they combine elements that can effectively improve health, even in non-responders. This review aims to explain the concept of synbiotics, highlight recent human clinical trials, and explore the current state of research on synergistic synbiotics.

Feasible mechanisms and therapeutic potential of food probiotics to mitigate diabetes‐associated cancers: A comprehensive review and in silico validation

People with diabetes mellitus (DM) and hyperglycemia are linked with cancer risk. Diabetes and cancer have been corroborated by high morbidity and mortality rates. Studies revealed that elevated levels of insulin secretions trigger insulin‐like growth factor 1 (IGF‐1) production. Moreover, IGF‐1 is a key regulator involved in promoting cancer cell progression and is linked with DM. Cancer drug resistance and ototoxic effects can adversely affect the health and lifespan of an individual. However, naturally derived bioactive compounds are gaining attention for their nontoxic properties and specific behavior. Likewise, probiotics have also been regarded as safe and successful alternatives to treat DM‐linked cancers. The present review aims to highlight the therapeutic potential and feasible functions of probiotics to mitigate or inhibit DM‐associated cancers. Meanwhile, the intracellular signaling cascades involved in promoting DM‐linked cancer are enumerated for future prospective research. However, metabolomics interactions and protein–protein interactions are to be discussed for deeper insights into affirmative principles in diabetic‐linked cancers. Drug discovery and innovative preclinical evaluation need further adjuvant and immune‐enhancement therapies. Furthermore, the results of the in silico assessment could provide scientific excellence of IGF‐1 in diabetes and cancer. Overall, this review summarizes the mechanistic insights and therapeutic targets for diabetes‐associated cancer.

Prebiotics, probiotics, synbiotics and postbiotics to adolescents in metabolic syndrome

The prevalence of childhood and adolescent obesity has globally reached alarming dimensions and many adolescents affected by obesity already present one or more obesity-related comorbidities. In recent years, emerging evidence supporting the role of gut microbiota in the pathophysiology of metabolic diseases has been reported and the use of prebiotics, probiotics, synbiotics and postbiotics as a strategy to manipulate gut microbiota has become popular. The aim of this review is to explore the relationship between gut microbiota and metabolic syndrome in adolescents and to discuss the potential use of prebiotics, probiotics, synbiotics and postbiotics for the prevention and treatment of this clinical picture in adolescence. According to the most recent literature, prebiotics, probiotics and synbiotics have no clear effect on MetS, but a possible modulation of anthropometric parameters has been observed after synbiotic supplementation. Only one study has examined the role of postbiotics in alleviating metabolic complications in children with obesity but not in adolescents. More extensive research is needed to support the conclusions drawn so far and to develop effective microbiome-based interventions that may help improving the quality of life of children and adolescents exposed to the increasing prevalence of MetS.

Prebiotics, Probiotics, and Synbiotics-A Research Hotspot for Pediatric Obesity

Childhood obesity is a major public health problem worldwide with an increasing prevalence, associated not only with metabolic syndrome, insulin resistance, hypertension, dyslipidemia, and non-alcoholic fatty liver disease (NAFLD), but also with psychosocial problems. Gut microbiota is a new factor in childhood obesity, which can modulate the blood lipopolysaccharide levels, the satiety, and fat distribution, and can ensure additional calories to the host. The aim of this review was to assess the differences and the impact of the gut microbial composition on several obesity-related complications such as metabolic syndrome, NAFLD, or insulin resistance. Early dysbiosis was proven to be associated with an increased predisposition to obesity. Depending on the predominant species, the gut microbiota might have either a positive or negative impact on the development of obesity. Prebiotics, probiotics, and synbiotics were suggested to have a positive effect on improving the gut microbiota and reducing cardio-metabolic risk factors. The results of clinical trials regarding probiotic, prebiotic, and synbiotic administration in children with metabolic syndrome, NAFLD, and insulin resistance are controversial. Some of them (Lactobacillus rhamnosus bv-77, Lactobacillus salivarius, and Bifidobacterium animalis) were proven to reduce the body mass index in obese children, and also improve the blood lipid content; others (Bifidobacterium bifidum, Bifidobacterium longum, Lactobacillus acidophilus, Lacticaseibacillus rhamnosus, Enterococcus faecium, and fructo-oligosaccharides) failed in proving any effect on lipid parameters and glucose metabolism. Further studies are necessary for understanding the mechanism of the gut microbiota in childhood obesity and for developing low-cost effective strategies for its management.