Effects of Different Dietary Models on Eating Behavior and Obesity Management in Overweight and Obese Individuals

NCT07055620 | Completed

• 1 other identifier: SBHORZUM
• Study Type: interventional
• Target: 75
• Locations: 1 country
• Sites: 1

Brief Summary

The aim of this study is to examine the effects of different diet models (Mediterranean diet, time-restricted feeding and standard diet application) applied to overweight and obese individuals on eating behavior and obesity management. Sub-objectives can be listed as; Effects of different diet models on body composition, Effects of different diet models on dietary intake, Effects of different diet models on biochemical parameters (such as blood sugar, insulin resistance, lipid profile). As a result, this study aims to contribute to the development of individualized nutrition counseling programs by determining effective diet strategies in obesity.

Conditions

Mediterranean Diet; Intermittent Fasting; Diet

Keywords

obesity; Mediterranean diet; intermittent fasting

Outcome Measures

Primary Outcomes (2)

• Diet Satisfaction Scale

  The validity and reliability study of the scale, originally named "Diet Satisfaction Scale", developed by Jospe and his colleagues in 2020, was conducted by Eskici and his colleagues in 2021 (Jospe et al 2020, Eskici and Yılmaz 2021). The items of the scale, which is used to evaluate issues such as hunger, desire to prepare food, enjoyment of the diet, following the diet at home and away from home, contribution to physical health, food variety, budget suitability and continuity, which affect the satisfaction of the clients with any diet, include 9-item five-point Likert-type (1=strongly disagree, 2=disagree, 3=undecided, 4=agree, 5=strongly agree) answer options. Only item 1 is scored in reverse (1=5, 2=4, 3=3, 4=2 and 5=1). The maximum score that can be obtained from the scale is 45. A high score indicates that diet satisfaction increases.

  12 weeks

• Three Factor Eating Questionnaire (TFEQ-21)

  In order to determine the eating behavior of the individuals participating in the study, the 21-item Three-Factor Eating Scale, which was validated for Turkish culture by Karakuş et al. in 2016, will be used. All of the items are four-point Likert-type and the answers are as follows; 1= Definitely false, 2= Mostly false, 3= Mostly true and 4= Definitely true. This scale measures eating behavior with three sub-dimensions: cognitive restraint (CRI), uncontrolled eating (URI) and emotional eating (EI). Items 1, 5, 11, 17, 18, and 21 measure CRI and evaluate the tendency to control food intake to maintain body weight and body shape. Items 3, 6, 8, 9, 12, 13, 15, 19, and 20 measure CRI and evaluate the tendency to lose control over eating when hungry and exposed to an external stimulus. EI; Items 2, 4, 7, 10, 14 and 16 measure and evaluate the relationship between a negative mood such as loneliness, demoralization or anxiety and overeating. It is recommended to use the converted scale scor

  12 weeks

Study Arms (3)

Mediterranean diet

ACTIVE COMPARATOR

Mediterranean diet

Other: Mediterranean diet

standard diet and time-restricted feeding

ACTIVE COMPARATOR

standard diet and time-restricted feeding

Other: standard diet and time-restricted feeding

control group

ACTIVE COMPARATOR

standard diet

Other: Standard diet

Interventions

Mediterranean diet OTHER

The group that will be applied the Mediterranean diet will be prepared with diet lists that include 35-40% carbohydrate, 15-20% protein and 35-45% fat (\>50% Monounsaturated Fatty Acid (MUFA)) of daily energy. The Mediterranean diet pyramid will be explained to the participants who will be applied the Mediterranean diet, and the portions and frequency of olive oil, nuts, olives, fish, yogurt, fruits and vegetables that they should consume will be planned by the dietitian. The Mediterranean diet pyramid recommends the frequency of foods that should be consumed daily, weekly and monthly. It recommends consuming fish and seafood at least twice a week, 2 portions of white meat, 2-4 portions of eggs, less than 2 portions of red meat, 1 portion or less of processed meat and less than 3 portions of dessert. It is recommended to consume 2 portions of dairy products, 1-2 portions of oil seeds and nuts, more spices, herbs, garlic and onions on a daily basis.

Mediterranean diet

Standard diet OTHER

When writing the weight loss diets applied to the individuals in the standard diet group, it will be taken into account that 45-60% of the energy comes from carbohydrates, 10-20% from protein and 20-35% from fat, as specified in the Turkish Nutrition Guide (TUBER). It will be planned that 10% (preferably 7-8%) of the total energy from fat will come from saturated fats (fat found in animal foods, butter, tallow, tail fat), 12-15% from monounsaturated fats (olive oil, hazelnut oil, rapeseed oil) and 7-10% from polyunsaturated fats (corn, soy, sunflower and cottonseed oils containing n-6 fatty acids and fish, fish oil, walnut, flaxseed containing n-3 fatty acids). It will be stated that this ratio is 1 part solid oil, 1 part any vegetable oil and 1.5 or 2 parts olive oil among the oil types.

control group

standard diet and time-restricted feeding OTHER

In time-restricted nutrition, the focus is on when the food is consumed rather than the type of food. However, in medical nutrition treatment of obesity, the content of the meals is also important along with the time (Soran and Öney 2022). As stated in the Turkish Nutrition Guide (TÜBER), it will be taken into account that 45-60% of the energy comes from carbohydrates, 10-20% from protein and 20-35% from fat (Ministry of Health, 2022). A time-restricted nutrition model will be implemented from intermittent fasting diet models. The time restriction will be planned as 8 hours of eating and 16 hours of fasting, suitable for the lifestyle of the individuals. The feeding time for individuals who agree to participate in the study will be determined as 11.00-12.00 and 19.00-20.00. Individuals will be given 2 main meals and the first meal will start with breakfast or lunch according to their wishes.

standard diet and time-restricted feeding

Eligibility Criteria

• Age: 20 Years - 49 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64)

You may qualify if:

• Being between 20-49 years old
• Having a BMI value between 25 kg/m2- 35 kg/m2
• Not having conditions that impair reality assessment ability and cognitive functions, preventing interviews or filling out scales
• Being literate
• Having a blood test done by a primary care physician within the last seven days
• Agreeing to participate in the study and signing the informed consent form

You may not qualify if:

• Pregnant and breastfeeding women,
• Those who could not attend one or more interview sessions,
• Women who have entered menopause,
• Individuals who want to apply another diet model,
• Individuals who have a pacemaker or defibrillator implanted due to the theoretical possibility of interference with device activity due to the current field caused by impedance measurements,
• Those who have any chronic disease and are on a diet,
• Those who regularly use medications that affect metabolism,
• Those who use insulin and oral antidiabetic medications,
• Those who have allergies or intolerances to any food components of the Mediterranean diet (walnuts, hazelnuts, peanuts, almonds, etc.),
• Those who use vitamin/mineral supplements,
• Those who have a psychiatric disease diagnosed by a physician.
• In order to understand the effectiveness of the diet, individuals will be asked to maintain their physical activity levels. Therefore, individuals who want to increase their physical activity levels in addition to the applied diet will not be included in the study.

Sponsors & Collaborators

• Selcuk University: lead

Study Sites (1)

Eda Ocak Nutrition and Diet Consultancy

Konya, Selçuklu, 42100, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Intermittent Fasting; Obesity

Interventions

Diet, Mediterranean

Condition Hierarchy (Ancestors)

Fasting; Feeding Behavior; Behavior; Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Diet, Plant-Based; Diet Therapy; Nutrition Therapy; Therapeutics; Diet; Nutritional Physiological Phenomena; Diet, Food, and Nutrition; Physiological Phenomena

Study Officials

• Ebru Bayrak

  Selcuk University

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: SUPPORTIVE CARE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: dietician

Model Details: The numbers assigned to the three different diet groups are as follows. Mediterranean Diet Group (1, 2, 6, 9, 13, 15, 18, 22, 24, 26, 29, 33, 37, 39, 41, 44, 47, 49, 52, 58, 63, 66, 69, 71, 75) Standard Diet Group (3, 7, 8, 11, 16, 19, 20, 23, 25, 30, 32, 34, 36, 40, 43, 45, 50, 51, 54, 56, 60, 62, 65, 68, 73 Time-Restricted Eating Group (4, 5, 10, 12, 14, 17, 21, 27, 28, 31, 35, 38, 42, 46, 48, 53, 55, 57, 59, 61, 64, 67, 70, 72, 74) Anthropometric measurements of the individuals participating in the study will be taken four times: at the beginning, at the 4th week, at the 8th week and at the 12th week.

Study Record Dates

• First Submitted: June 19, 2025
• First Posted: July 9, 2025
• Study Start: April 18, 2025
• Primary Completion: June 18, 2025
• Study Completion: November 12, 2025
• Last Updated: November 25, 2025

Record last verified: 2025-11

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, ICF
• Time Frame: April 2025-November 2025
• Access Criteria: Access criteria will be shared with researchers who meet the following conditions: Being employed by a recognized academic institution, university, research hospital, or public research organization; Providing documentation that the study in which the requested data will be used has scientific, ethical, and social benefit purposes; Submitting a research protocol approved by the relevant institution or ethics committee; Committing that the data will be used only for secondary analysis or meta-analysis.

Locations

TU (1)