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

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.

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