Comparing Intermittent Fasting and Mediterranean Diet for Obesity

Comparative Effects of Intermittent Fasting Versus Mediterranean Diet on Obesity Management: A Randomized Controlled Trial

Purpose: This study aimed to evaluate and compare the effects of intermittent fasting (IF) and the Mediterranean diet (MD) on weight loss in obese adults.

Methods: A total of 120 adults diagnosed with obesity were enrolled. Baseline data on physical activity and dietary intake were collected through structured interviews. Participants were randomly assigned to two groups for a 4-week intervention. The IF group followed a time-restricted eating schedule (16:8), while the MD group followed a structured plan of three main meals and three snacks daily. Both diets included a 500-calorie daily reduction from estimated energy needs. Anthropometric measurements were recorded at baseline and week 4.

Study Overview

• Status: Completed
• Conditions: Weight Loss
• Intervention / Treatment: Other: Intermittent Fasting Diet; Other: Mediterranean Diet

• Study Type: Interventional
• Enrollment (Actual): 120
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Cyprus
  • Lefka, Cyprus, 99770
    • European University of Lefke

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• BMI ≥ 30 kg/m²
• absence of chronic diseases
• no regular use of medications
• non smokers
• non alcohol users
• not pregnant or breastfeeding
• no history of bariatric surgery
• no significant weight fluctuations (±5 kg) in the past 6 months
• no pregnancy plans during the study period

Exclusion Criteria:

• BMI < 30 kg/m²
• Presence of any diagnosed chronic disease (e.g., diabetes, cardiovascular disease, thyroid disorders, renal or hepatic disease)
• Regular use of medications that could affect metabolism, appetite, or body weight
• Smoking or alcohol consumption
• Pregnancy or breastfeeding during the study period
• History of bariatric or other weight-related surgical procedures
• Significant weight changes (gain or loss ≥5 kg) within the past 6 months
• Planning pregnancy during the study period
• Inability or unwillingness to comply with dietary intervention and follow-up requirements

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: intermittent fasting diet intervention group; 4 week time restricted intermittent fasting diet protocol	Other: Intermittent Fasting Diet; Participants follow a time-restricted eating pattern for 4 weeks, consuming all meals within an 8-hour eating window (from 1:00 PM to 9:00 PM) and fasting for the remaining 16 hours each day. During the feeding window, they consume two main meals and one snack based on ad libitum intake, without specific calorie restriction. Dietary guidance is provided at the start and mid-point of the protocol by a registered dietitian.
Experimental: Mediterranean diet intervention group; 4 week mediterranean diet protocol	Other: Mediterranean Diet; Participants follow a 4-week Mediterranean diet protocol that is adapted from the PREDIMED criteria and the MedDietScore index. The diet emphasizes high consumption of vegetables, fruits, legumes, whole grains, nuts, and olive oil; moderate intake of fish and poultry; and limited consumption of red meat, dairy products, and sweets. A registered dietitian provides dietary counseling sessions at the beginning and midway through the intervention.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body weight (kg)	Body weight is measured with using the TANITA BC-418 body composition analyzer. Participants are weighed barefoot, in light clothing, and measurements are recorded in kilograms.	Baseline and Week 4

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body Mass Index (kg/m²)	BMI is computed as weight in kilograms divided by height in meters squared (kg/m²)	Baseline and Week 4

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body height (cm)	Height is measured once at baseline using a wall-mounted stadiometer. Participants stand barefoot, with heels together, arms at the sides, and head positioned in the Frankfurt horizontal plane. The measurement is recorded to the nearest 0.1 centimeter and converted to meters.	Baseline only
Body Fat Percentage	Body fat percentage is measured at baseline and Week 4 using the TANITA BC-418 body composition analyzer	Baseline and week 4
Fat Free Mass (kg)	Fat free mass is assessed using bioelectrical impedance analysis with TANITA BC-418	Baseline and Week 4
Total Body Water Percentage	Total body water percentage is assessed using bioelectrical impedance analysis with TANITA BC-418.	Baseline and Week 4
Waist Circumference (cm)	Waist circumference is measured using a non-elastic, flexible measuring tape. The measurement is taken at the midpoint between the lower margin of the last palpable rib and the top of the iliac crest, while the participant stands upright with feet close together and breathes out normally.	Baseline and Week 4
Hip Circumference (cm)	Hip circumference is measured with using a non-elastic measuring tape. The measurement is taken around the widest portion of the buttocks, with the participant standing upright and feet together.	Baseline and Week 4

Collaborators and Investigators

• Sponsor: Kamil Dağcılar

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2022
• Primary Completion (Actual): December 25, 2022
• Study Completion (Actual): December 30, 2022

Study Registration Dates

• First Submitted: November 14, 2025
• First Submitted That Met QC Criteria: November 18, 2025
• First Posted (Actual): November 26, 2025

Study Record Updates

• Last Update Posted (Actual): November 26, 2025
• Last Update Submitted That Met QC Criteria: November 18, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: obesity; weight loss; intermittent fasting; mediterranean diet
• Additional Relevant MeSH Terms: Nutrition Disorders; Overnutrition; Body Weight; Body Weight Changes; Overweight; Pathological Conditions, Signs and Symptoms; Behavior; Nutritional and Metabolic Diseases; Signs and Symptoms; Feeding Behavior; Fasting; Obesity; Weight Loss; Intermittent Fasting; Therapeutics; Diet, Food, and Nutrition; Physiological Phenomena; Nutritional Physiological Phenomena; Diet, Plant-Based; Diet Therapy; Nutrition Therapy; Diet; Diet, Mediterranean
• Other Study ID Numbers: BAYEK011.02

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP; ICF; ANALYTIC_CODE; CSR

Drug and device information, study documents

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