Effect of Polysaccharide-based Complex Administration on the Gut Microbiome and Cardio-Metabolic Profile in Children With Obesity and Metabolic Syndrome. (Polymets)

Childhood obesity is a growing public health concern and is associated with long-term health issues. Changing lifestyle habits, especially improving diet and maintaining these changes over time, can be challenging for children and families. For this reason, new treatment options are being explored, including ways to improve the gut microbiota, which can influence appetite and host metabolic health.

This study will investigate the impact of a medical device made of polysaccharide-based complex together with healthy lifestyle and dietary intervention, on gut microbiota composition and metabolic health in children and adolescents with metabolically unhealthy obesity. The study will last 8 months and will include 3 visits: at the start (T0), after 4 months (T1), and after 8 months (T2). From T0 to T1, participants will receive the polysaccharide-based complex along with Mediterranean-style dietary and behavioral intervention. From T1 to T2, only the dietary-lifestyle program will continue.

At each visit, researchers will collect blood samples, perform nutritional and body composition assessment, and collect stool samples to characterise the gut microbiota. The primary aim is to evaluate the effect on gut microbiota composition of a polysaccharide-based complex administration combined with dietary and lifestyle interventions. Furthermore, the study aims to evaluate the effectiveness of this intervention in improving obesity-related parameters and the overall cardiometabolic profile.

Study Overview

• Status: Completed
• Conditions: Childhood Obesity
• Intervention / Treatment: Device: Polysaccharide-based complex

• Study Type: Interventional
• Enrollment (Actual): 36
• Phase: Phase 4

Contacts and Locations

Study Locations

• Italy
  • Milan, Italy, 20154
    • Department of Pediatrics, Vittore Buzzi Children's Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• age 8 to 14 years;
• obesity defined as BMI z-score ≥+2 standard deviation scores (SDS) based on the WHO growth charts
• gestational age 37-42 weeks;
• birth weight >2500 g and <4000 g;

• established condition of MUO, defined as follows:

  1. for children ≤10 years according to the IDEFICS criteria [waist circumference (WC) ≥90th percentile and ≥1 of the followings triglycerides (TG) ≥90th percentile, HDL cholesterol (HDL) ≤10th percentile, systolic blood pressure (SBP) or diastolic blood pressure (DBP) ≥90th percentile, HOMA-insulin resistance ≥90th percentile or fasting glucose ≥90th percentile];
  2. for children >10 years according to the IDF criteria [WC ≥ 90th percentile and ≥1 of the followings TG ≥ 150 mg/Dl, HDL ≤ 40 mg/dL, SBP ≥ 130 mmHg, DBP ≥ 85 mmHg and fasting blood glucose ≥ 100 mg/dl or known Type 2 Diabetes]

Exclusion Criteria:

• diagnosis of secondary obesity;
• treatment with pre/probiotics in the previous 3 months;
• antibiotic treatment in the previous 3 months;
• presence of chronic or acute intestinal disease in the previous 3 months

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Single-arm Pre-Post Treatment; At T0 (enrollment), participants will undergo baseline assessments. From T0 to T1, they will receive a polysaccharide-based complex together with a dietary and lifestyle intervention based on Mediterranean diet principles. From T1 to T2, the polysaccharide-based complex will be discontinued, and participants will continue only with the dietary and lifestyle intervention as a washout phase. Assessments at T0, T1, and T2 will be used to evaluate changes over time.

Device: Polysaccharide-based complex; The Polysaccharide-based complex is a medical device composed of mixture of soluble and insoluble fibres (cellulose, hemicellulose, pectin, mucilages). After enrolment at T0, participants were instructed to consume a polysaccharide-based complex for 4 months at a dosage of two sachets daily, to be consumed one before lunch and one before dinner (total 5 g/day).; Other Names: Neo-Policaptil Gel Retard

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
gut microbiota composition	Collection of fecal samples, bacterial DNA extraction and analysis of V3-V4 hypervariable regions of the prokaryotic 16S ribosomal RNA (rRNA) gene	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Weight	Body weight Description: Body weight measured in kilograms using a calibrated scale. Unit of Measure: kg	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Height	Height Description: Standing height measured using a stadiometer. Unit of Measure: cm	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Height z-score	Height z-score Description: Height-for-age z-score calculated according to reference growth charts. Unit of Measure: z-score	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Body Mass Index	Body Mass Index (BMI) Description: weight and height will be combined to report BMI in kg/m^2 Unit of measure: kg/m^2	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Body Mass Index z-score	BMI z-score Description: BMI-for-age z-score calculated according to reference growth charts. Unit of Measure: z-score	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Waist circumference	Waist circumference Description: : Waist circumference measured in centimeters using a non-elastic measuring tape. Unit of Measure: cm	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Waist-to-height ratio	Waist-to-height ratio Description: : Waist-to-height ratio calculated as waist circumference divided by height. Unit of Measure: unitless ratio	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Fat mass (kg)	Total body fat mass expressed in kilograms, assessed using air plethysmography. Unit of Measure: kg	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Fat mass (%)	Percentage of total body fat relative to body weight, assessed using air plethysmography. Unit of Measure: %	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Fat free mass (kg)	Total fat-free mass expressed in kilograms, assessed using air plethysmography. Unit of Measure: kg	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Fat free mass (%)	Percentage of fat-free mass relative to body weight, assessed using air plethysmography. Unit of Measure: %	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Systolic blood pressure	Systolic blood pressure measured in millimeters of mercury using a calibrated sphygmomanometer. Unit of Measure: mmHg	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Diastolic blood pressure	Diastolic blood pressure measured in millimeters of mercury using a calibrated sphygmomanometer. Unit of Measure: mmHg	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Fasting glucose	Fasting plasma glucose concentration measured in venous blood samples. Unit of Measure: mg/dL	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Fasting insulin	Fasting plasma insulin concentration measured in venous blood samples. Unit of Measure: µU/mL	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Glycated hemoglobin (HbA1c)	Glycated hemoglobin (HbA1c) concentration measured in whole blood as an indicator of long-term glycemic control. Unit of Measure: mmol/mol	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Lipid profile	Fasting serum lipid concentrations including total cholesterol, LDL cholesterol, HDL cholesterol, and triglycerides. Each lipid parameter will be analyzed and reported separately. Unit of Measure: mg/dL	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Liver enzymes	Serum liver enzyme concentrations including aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Each enzyme will be analyzed and reported separately. Unit of Measure: U/L	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Homeostatic Model Assessment of Insulin Resistance (HOMA-IR)	Insulin resistance assessed using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), calculated from fasting plasma glucose and fasting plasma insulin concentrations. Unit of Measure: index value	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Quantitative Insulin Sensitivity Check Index (QUICKI)	Insulin sensitivity assessed using the Quantitative Insulin Sensitivity Check Index (QUICKI), calculated from fasting plasma glucose and fasting plasma insulin concentrations. Unit of Measure: index value	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Triglyceride-Glucose (TyG) index	Insulin resistance assessed using the Triglyceride-Glucose (TyG) index, calculated from fasting triglyceride and fasting plasma glucose concentrations. Unit of Measure: index value	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Atherogenic Index of Plasma (AIP)	Atherogenic risk assessed using the Atherogenic Index of Plasma (AIP), calculated as the logarithm of the ratio between triglycerides and HDL cholesterol concentrations. Unit of Measure: index value	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Energy Intake	Energy intake Unit: kcal/day	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Macronutrient intake (grams/day)	Daily intake of macronutrients expressed in grams per day, including: carbohydrates,; sugars,; total dietary fibers,; insoluble fibers,; soluble fibers,; proteins,; animal proteins,; plant proteins,; total lipids,; saturated fatty acids,; monounsaturated fatty acids,; polyunsaturated fatty acids, Each macronutrient will be analyzed and reported separately. Unit of Measure: g/day	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Macronutrient intake (% of energy)	Contribution of macronutrients to total energy intake expressed as percentage of energy, including: carbohydrates,; sugars,; proteins,; total lipids,; saturated fatty acids,; monounsaturated fatty acids,; polyunsaturated fatty acids,; omega-3 fatty acids,; omega-6 fatty acids. Each macronutrient will be analyzed and reported separately. Unit of Measure: % of daily energy intake (%En)	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Micronutrients (µg/day)	Daily intake of vitamin B12 and folic acid expressed in micrograms per day. Unit of Measure: µg/day	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Micronutrients (mg/day)	Daily intake of calcium, iron, zinc, and magnesium expressed in milligrams per day. Unit of Measure: mg/day	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
KIDMED score	Adherence to the Mediterranean diet assessed using the KIDMED questionnaire (score range 0-12). Unit of Measure: score	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mid-upper arm circumference (MUAC)	Mid-upper arm circumference (MUAC) Description: : Mid-upper arm circumference measured in centimeters using a non-elastic measuring tape. Unit of Measure: cm	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Mid-upper arm circumference (MUAC) z-score	Mid-upper arm circumference (MUAC) z-score Description: Mid-upper arm circumference-for-age z-score calculated according to reference growth standards. Unit of Measure: z-score	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Triceps skinfold thickness	Triceps skinfold thickness measured in millimeters using a calibrated skinfold caliper.. Unit of Measure: mm	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Triceps skinfold thickness z-score	Triceps skinfold thickness-for-age z-score calculated according to reference growth standards. Unit of Measure: z-score	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)
Presence of MASLD	Description: Presence of metabolic dysfunction-associated steatotic liver disease (MASLD) assessed by abdominal ultrasound. Measure Type: Dichotomous (Yes/No)	At enrollment (T0), after 4 months (T1), at the end of the study at 8 months (T2)

Collaborators and Investigators

• Sponsor: University of Milan
• Collaborators: ASST Fatebenefratelli Sacco

Publications and helpful links

General Publications

• Serra-Majem L, Ribas L, Ngo J, Ortega RM, Garcia A, Perez-Rodrigo C, Aranceta J. Food, youth and the Mediterranean diet in Spain. Development of KIDMED, Mediterranean Diet Quality Index in children and adolescents. Public Health Nutr. 2004 Oct;7(7):931-5. doi: 10.1079/phn2004556.
• Altavilla C, Caballero-Perez P. An update of the KIDMED questionnaire, a Mediterranean Diet Quality Index in children and adolescents. Public Health Nutr. 2019 Oct;22(14):2543-2547. doi: 10.1017/S1368980019001058. Epub 2019 May 31.
• Stagi S, Lapi E, Seminara S, Pelosi P, Del Greco P, Capirchio L, Strano M, Giglio S, Chiarelli F, de Martino M. Policaptil Gel Retard significantly reduces body mass index and hyperinsulinism and may decrease the risk of type 2 diabetes mellitus (T2DM) in obese children and adolescents with family history of obesity and T2DM. Ital J Pediatr. 2015 Feb 15;41:10. doi: 10.1186/s13052-015-0109-7.
• Zimmet P, Alberti KG, Kaufman F, Tajima N, Silink M, Arslanian S, Wong G, Bennett P, Shaw J, Caprio S; IDF Consensus Group. The metabolic syndrome in children and adolescents - an IDF consensus report. Pediatr Diabetes. 2007 Oct;8(5):299-306. doi: 10.1111/j.1399-5448.2007.00271.x. No abstract available.
• Ahrens W, Moreno LA, Marild S, Molnar D, Siani A, De Henauw S, Bohmann J, Gunther K, Hadjigeorgiou C, Iacoviello L, Lissner L, Veidebaum T, Pohlabeln H, Pigeot I; IDEFICS consortium. Metabolic syndrome in young children: definitions and results of the IDEFICS study. Int J Obes (Lond). 2014 Sep;38 Suppl 2:S4-14. doi: 10.1038/ijo.2014.130.
• Damanhoury S, Newton AS, Rashid M, Hartling L, Byrne JLS, Ball GDC. Defining metabolically healthy obesity in children: a scoping review. Obes Rev. 2018 Nov;19(11):1476-1491. doi: 10.1111/obr.12721. Epub 2018 Aug 28.

Study record dates

Study Major Dates

• Study Start (Actual): February 1, 2022
• Primary Completion (Actual): November 30, 2023
• Study Completion (Actual): November 30, 2024

Study Registration Dates

• First Submitted: November 25, 2025
• First Submitted That Met QC Criteria: December 27, 2025
• First Posted (Actual): January 6, 2026

Study Record Updates

• Last Update Posted (Actual): January 6, 2026
• Last Update Submitted That Met QC Criteria: December 27, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: childhood obesity; gut microbiota; metabolic syndrome; mediterranean diet; fiber
• Additional Relevant MeSH Terms: Nutrition Disorders; Metabolic Diseases; Overnutrition; Body Weight; Glucose Metabolism Disorders; Insulin Resistance; Hyperinsulinism; Overweight; Obesity; Pathological Conditions, Signs and Symptoms; Nutritional and Metabolic Diseases; Signs and Symptoms; Metabolic Syndrome; Pediatric Obesity
• Other Study ID Numbers: 2021/ST/260; Ethical Committe (Other Identifier: Comitato Etico Milano Area 1)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: No individual participant data will be shared because the study involves minors

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No