The Effects of the Mediterranean Diet and Synbiotics in Polycystic Ovary Syndrome

January 6, 2026 updated by: Aysenur Emirhuseyinoglu Calik, Atlas University

Effects of a Mediterranean Diet and Synbiotic Supplementation on Anthropometric and Biochemical Parameters and Quality of Life in Obese Women With Polycystic Ovary Syndrome

This study will look at whether a reduced-calorie Mediterranean-style eating plan, together with a synbiotic supplement, can improve health measures and quality of life in women who have polycystic ovary syndrome (PCOS) and are overweight or have obesity. Participants will be assigned by chance (like flipping a coin) to receive either the synbiotic supplement or a placebo (a look-alike product with no active ingredients). All participants will follow the same reduced-calorie Mediterranean diet for 8 weeks. The study team will measure body composition and weight-related measurements, and will collect blood samples to evaluate selected laboratory markers before and after the 8-week period. Participants will also complete the PCOSQ-50 quality-of-life questionnaire before and after the intervention. The goal is to better understand the possible role of synbiotic supplementation alongside dietary treatment in PCOS.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

This randomized, placebo-controlled, single-blind clinical trial is designed to evaluate the effects of a hypocaloric Mediterranean diet combined with synbiotic supplementation on anthropometric measurements, biochemical parameters, and quality of life in overweight and obese women diagnosed with polycystic ovary syndrome (PCOS). Eligible participants will be randomly assigned to one of two study arms: a synbiotic supplementation group or a placebo group. Both groups will follow the same hypocaloric Mediterranean diet throughout the 8-week intervention period.

Anthropometric assessments, including body weight, body mass index, waist circumference, and body composition, will be performed at baseline and at the end of the intervention. Biochemical parameters will be evaluated through blood samples collected at baseline and after 8 weeks. Quality of life will be assessed using the PCOSQ-50 Quality of Life Questionnaire at both time points.

The study aims to determine whether the addition of synbiotic supplementation to a hypocaloric Mediterranean diet provides additional benefits in the management of PCOS-related metabolic parameters and quality of life compared with dietary intervention alone.

Study Type

Interventional

Enrollment (Estimated)

32

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Premenopausal women who are overweight or obese, with a body mass index (BMI) between 25 and 35 kg/m²
  • Aged 18 to 45 years (reproductive age)
  • Diagnosed with polycystic ovary syndrome (PCOS)

No underlying metabolic diseases, including type 2 diabetes mellitus, hypertension, diagnosed anemia, or any other metabolic condition requiring a special diet

Exclusion Criteria:

  • Pregnancy or breastfeeding within the past 6 months
  • Presence of comorbid conditions, including kidney, liver, or cardiovascular disease, gout, hyperuricemia, or other related disorders
  • Use of oral contraceptives
  • Following a special dietary treatment or a hypocaloric diet within the last 3 months
  • Occasional or current use of medications that may affect fluid balance, including diuretics and laxatives
  • Participants will be withdrawn from the study in case of abnormal biochemical parameters, non-adherence to the prescribed diet, or failure to comply with the supplementation protoco

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Single

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Placebo Comparator: Placebo
Participants in this arm will receive a hypocaloric Mediterranean diet in addition to a placebo for a period of 8 weeks.
Other: Placebo
Participants in this arm will receive a hypocaloric Mediterranean diet in addition to a placebo for a period of 8 weeks.
Other Names:
  • Mediterrenean Diet
Active Comparator: Synbiotics
Participants in this arm will receive a hypocaloric Mediterranean diet in addition to synbiotic supplementation for a period of 8 weeks.
Dietary supplement: Synbiotic Supplement
Participants in this arm will receive a hypocaloric Mediterranean diet in addition to synbiotic supplementation for a period of 8 weeks.
Other Names:
  • Mediterrenean Diet

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in body weight
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in body weight measured in kilograms using the Tanita MC-780 bioelectrical impedance analysis (BIA) device at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in body mass index (BMI)
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in body mass index (BMI), calculated as weight in kilograms divided by height in meters squared (kg/m²), with body weight measured using the Tanita MC-780 bioelectrical impedance analysis (BIA) device at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in body composition
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in body composition parameters, including fat mass and fat-free mass, assessed using the Tanita MC-780 bioelectrical impedance analysis (BIA) device at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in waist circumference
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in waist circumference measured in centimeters using a non-elastic measuring tape at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in hip circumference
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in hip circumference measured in centimeters using a non-elastic measuring tape at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in insulin resistance (HOMA-IR)
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in insulin resistance assessed using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR), calculated from fasting plasma glucose and fasting insulin levels. A HOMA-IR value below 2.5 will be considered indicative of the absence of insulin resistance. Measurements will be performed at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in fasting blood glucose
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in fasting blood glucose levels measured in mg/dL from venous blood samples collected at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in lipid profile
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in serum lipid profile parameters, including high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), and total cholesterol, measured in mg/dL from venous blood samples collected at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in follicle-stimulating hormone (FSH) levels
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in serum follicle-stimulating hormone (FSH) levels measured from venous blood samples collected at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in luteinizing hormone (LH) levels
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in serum luteinizing hormone (LH) levels measured from venous blood samples collected at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks
Change in quality of life
Time Frame: From enrollment to the end of treatment at 8 weeks
Changes in quality of life assessed using the Polycystic Ovary Syndrome Quality of Life Questionnaire (PCOSQ-50), a validated disease-specific instrument consisting of 50 items across six domains: psychosocial and emotional well-being, fertility, sexual function, obesity and menstrual irregularity, hirsutism, and coping with the disease. Each item is scored on a 5-point Likert scale ranging from 1 (always) to 5 (never), resulting in a total score range of 50 to 250. Higher scores indicate better quality of life. Domain scores are calculated as the mean of the items answered within each domain, excluding unanswered items. Assessments will be performed at baseline and after the 8-week intervention.
From enrollment to the end of treatment at 8 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Atlas University

Investigators

  • Study Director: Derya Sivri-Aydın, Atlas University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

December 20, 2025

Primary Completion (Estimated)

April 1, 2027

Study Completion (Estimated)

August 1, 2027

Study Registration Dates

First Submitted

December 23, 2025

First Submitted That Met QC Criteria

January 6, 2026

First Posted (Actual)

January 15, 2026

Study Record Updates

Last Update Posted (Actual)

January 15, 2026

Last Update Submitted That Met QC Criteria

January 6, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • E-22686390-050.99-78501

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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