Effects of Boron and Mediterranean Diets on Gut Microbiota and Metabolic Health

Not Applicable

Completed

• Conditions: Obesity; Dietary Intervention; Gut Microbiota; Cardiometabolic Risk Factors; Appetite-Regulating Hormones

• Registration Number: NCT07156097
• Lead Sponsor: Dicle University

Brief Summary

This study investigated the effects of a boron-rich diet compared with a Mediterranean-style diet (Smart Alternative Food Formulation; SAFF) on obesity-related outcomes in adults. Forty obese participants were randomly assigned to receive either a boron-rich diet or the SAFF diet for four weeks. Anthropometric measurements, biochemical parameters, and adipokine levels were evaluated before and after the intervention.

The primary aim was to determine whether dietary boron intake can improve metabolic health, lipid profile, and obesity-related hormonal regulation compared to a widely accepted dietary model. Findings from this trial may contribute to understanding the potential role of boron and diet-microbiota interactions in obesity management and provide evidence for future nutritional strategies.

Detailed Description

This single-center, prospective, randomized controlled clinical trial was conducted to investigate the effects of a boron-rich diet compared to a Mediterranean-style diet (SAFF) on obesity, metabolic parameters, and gut microbiota composition in adults with obesity. The trial was carried out at Dicle University, Diyarbakır, Turkey, over a 4-week intervention period.

A total of 40 obese participants (Body Mass Index \[BMI\] ≥30 kg/m²), aged 18-65 years, were enrolled following eligibility screening. Inclusion criteria comprised clinically stable individuals without severe systemic disease, no recent antibiotic or probiotic use within the past month, and willingness to comply with dietary instructions. Exclusion criteria included pregnancy or lactation, use of medications affecting weight or metabolism, history of gastrointestinal surgery, or presence of chronic inflammatory diseases.

Participants were randomized into two groups:

Boron-Rich Diet Group (n=20): Participants received a structured diet plan enriched with natural boron sources (such as dried fruits, nuts, legumes, and selected vegetables), formulated to provide a daily boron intake aligned with nutritional safety guidelines.

SAFF (Mediterranean-Style) Diet Group (n=20): Participants followed a diet rich in olive oil, whole grains, legumes, fruits, vegetables, and moderate fish consumption, consistent with Mediterranean dietary principles.

Both groups received equivalent calorie prescriptions tailored to individual energy requirements to promote weight reduction while ensuring comparable macronutrient distribution. Participants received weekly dietary counseling to ensure adherence.

Outcome Measures:

Primary Outcomes: Changes in anthropometric parameters (body weight, BMI, waist circumference) and biochemical markers (lipid profile, fasting glucose, insulin, Homeostatic Model Assessment for Insulin Resistance \[HOMA-IR\]).

Secondary Outcomes: Serum adipokines (leptin, adiponectin), inflammatory biomarkers, and gut microbiota composition assessed through stool sampling and next-generation sequencing.

Statistical analysis was performed using appropriate parametric or non-parametric tests depending on distribution. Effect sizes and 95% confidence intervals were reported to evaluate the magnitude of differences.

Ethical approval for the study was granted by the Non-Interventional Research Ethics Committee of Firat University (Decision No: 2023/01-19). The trial was conducted in accordance with the principles of the Declaration of Helsinki. Written informed consent was obtained from all participants.

This study contributes novel clinical evidence regarding the potential role of boron-enriched diets as a nutritional intervention for obesity management and provides insights into the diet-microbiota-metabolism relationship.

Study Timeline

• Study Start: 2023-01-05
• Primary Completion: 2023-02-02
• Study Completion: 2023-03-15
• Study First Submitted: 2025-08-20
• Status Verified: 2025-09
• Study First Submitted QC: 2025-09-03
• Last Update Submitted: 2025-09-03
• Study First Posted: 2025-09-04
• Last Update Posted: 2025-09-04

Recruitment & Eligibility

• Status: COMPLETED
• Sex: Female
• Target Recruitment: 40

Inclusion Criteria

• Female participants aged 18-65 years
• Body Mass Index (BMI) ≥30 kg/m² (diagnosis of obesity)
• Willingness to participate in the 4-week dietary intervention
• Ability to provide written informed consent

Exclusion Criteria

• Presence of chronic diseases (e.g., diabetes, cardiovascular disease, renal disease, gastrointestinal disorders)
• Current use of medications or dietary supplements affecting weight, metabolism, or gut microbiota
• Use of probiotics, prebiotics, or commercial weight loss products in the past 3 months
• Pregnancy or lactation
• Known food allergies or intolerances incompatible with the prescribed diets
• Inability to comply with study procedures or dietary intervention

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Primary Outcome Measures

Name	Time	Method
Change in Body Mass Index	Baseline to 4 weeks	BMI will be calculated as weight (kg) divided by height (m²). Weight will be measured using a calibrated digital scale and height with a stadiometer by trained staff following standardized procedures. The between-group difference in BMI change will be assessed to evaluate the effect of the interventions on obesity outcomes.
Change in Gut Microbiota Diversity	Baseline to 4 weeks	Stool samples will be collected at baseline and 4 weeks. 16S rRNA gene sequencing will be performed; alpha diversity will be calculated using the Shannon Index. Higher values indicate greater within-sample diversity.

Secondary Outcome Measures

Name	Time	Method
Change in Serum Leptin Level	Baseline to 4 weeks	Fasting venous blood will be collected in the morning. Serum leptin will be quantified using a validated ELISA kit according to the manufacturer's instructions. Changes will be analyzed within and between diet arms.
Change in Low-Density Lipoprotein Cholesterol	Baseline to 4 weeks	Fasting lipid profile will be measured using an automated analyzer in the central laboratory. LDL-C will be calculated directly or via the Friedewald equation when applicable. The outcome represents the change in LDL-C from baseline to end of intervention.

Trial Locations

Locations (1)

Feray Çağıran Yılmaz; Diyarbakır, Diyarbakır, Turkey (Türkiye)