Plant-Based Foods and (Poly)Phenol Supplementation in Gut Microbiota Modulation, Body Weight, and Cardiometabolic Risk

Summary

This single-blind, randomized controlled trial aims to evaluate the effects of increased dietary polyphenol intake-either through a healthy plant-based diet (PBD) or supplementation-on body weight and cardiometabolic risk factors in adults with overweight or obesity.

A total of 99 participants (aged 25-45 years, BMI 25-35 kg/m²) with cardiovascular risk factors will be recruited from local health centers and randomly assigned (1:1:1) to one of three intervention groups for 12 weeks: (1) a healthy PBD rich in polyphenols, with supplemental apple, blueberries, hazelnuts, extra-virgin olive oil, and coffee provided at no cost to the participant (2) a healthy diet plus polyphenol supplementation (≈30g/day) from maqui , green tea, olive leaf, cranberry, and grape extracts, or (3) a control group receiving placebo and standard healthy diet recommendations. All groups will follow a caloric deficit.

Dietary intake will be assessed using three 24-hour dietary recalls at baseline and 12 weeks, with polyphenol intake estimated via the Phenol-Explorer database. Data collection will include lifestyle questionnaires, anthropometric and bioimpedance measurements, blood pressure assessments, physical activity monitoring via accelerometers, and strength evaluations. Blood samples will be analyzed using a large-scale targeted metabolomics approach (UHPLC-MS/MS) to identify metabolic signatures, particularly those linked to gut microbiota. Faecal samples will be collected at baseline and visit 3.

Findings will provide insights into how dietary polyphenols-either from whole foods or supplementation-affect obesity-related outcomes and cardiometabolic risk, potentially unveiling gut microbial biomarkers as future therapeutic targets. This study aims to contribute to strategies for obesity and cardiometabolic risk prevention and treatment.

Conditions

• Obesity and Overweight

Interventions

DIETARY_SUPPLEMENT

Diet supplementation

Healthy plant-based diet (plus supplemental foods) as part of a hypocaloric diet.

DIETARY_SUPPLEMENT

Polyphenol-rich supplement

Hypocaloric diet with polyphenol-rich supplement. Polyphenol-rich sachets containing ≈30g/day of a combination of plant extracts rich in polyphenol. Frequency: 2 sachets a day. Duration: 12 weeks

OTHER

Placebo

Hypocaloric diet plus Placebo. The placebo is a sachet (≈30g/day) with similar appearance, taste, and texture but without active polyphenols. Frequency: 2 sachets a day. Duration: 12 weeks

Sponsors & Collaborators

• Agencia Nacional de Investigación y Desarrollo

  collaborator OTHER

• Universidad Catolica de Temuco

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

25 Years

Max Age

45 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2025-07-21

Primary Completion

2026-06-03

Completion

2026-06-03

Countries

• Chile

Study Locations