The Effect of Mediterranean Diet and Mindfulness Eating on Depression Severity in People With Obesity and Major Depressive Disorder

Not Applicable

Recruiting

• Conditions: Depressive Disorder, Major
• Interventions: Other: nutritional intervention; Behavioral: Mindful Eating; Other: Attention Control

• Registration Number: NCT06621394
• Lead Sponsor: University Hospital Tuebingen

Brief Summary

The present study investigates the effect of Mediterranean Diet and Mindful Eating on depression severity in people with obesity and major depressive disorder. The factorial design allows to investigate potential synergistic effects of the interventions. Participants will be randomized to one of the four intervention groups (mediterranean diet, mindful eating, their combination and a befriending control group). The intervention consists of a 12-week period, followed by a 12-week follow up. The primary outcome is depression severity.

Detailed Description

Depression and obesity are highly prevalent diseases that are strongly correlated. There is a growing gap in care and treatment options for those affected. The effectiveness of a Mediterranean Diet on mental health has already been shown in various studies. Additionally to physiological effects of nutrient intake, also the psychological factor of changing the way of eating seem to play a role. The present study investigates the effect of a Mediterranean Diet and Mindful Eating on depression severity in people with obesity and clinically diagnosed major depressive disorder. The factorial design allows to investigate potential synergistic effects of the interventions. Participants will be randomized to one of the four intervention groups (mediterranean diet, mindful eating, their combination and a befriending control group). The intervention consists of a 12-week period, where five individual nutrition consueling meetings will take place, followed by a 12-week follow up. The primary outcome is depression severity. Secondary outcomes and analyzes include quality of life, self-efficacy, mediterranean diet and mindfulness eating scores, anthropometric measurements, as well as mediator and moderator analysis, a microbiome analysis, a qualitative evaluation and an economic analysis.

Study Timeline

• Study First Submitted: 2024-09-23
• Study First Submitted QC: 2024-09-27
• Study First Posted: 2024-10-01
• Status Verified: 2024-11
• Study Start: 2024-11-05
• Primary Completion: 2025-03-01
• Last Update Submitted: 2025-04-03
• Last Update Posted: 2025-04-08
• Study Completion: 2025-09-01

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 64

Inclusion Criteria

• Age ≥ 18 years
• Presence of clinically diagnosed major depression
• At least moderate depression severity: BDI-II ≥ 20
• obesity: BMI ≥ 30 kg/m2
• Stable co-intervention: no change in the type, dosage or frequency of antidepressant medication and/or psychotherapy four weeks before and during the study
• Low adherence to the mediterranean diet: MEDAS < 10
• Low adherence to mindful eating: MEI < 5.13

Exclusion Criteria

• Diseases of the gastrointestinal tract that do not allow adequate implementation of the intervention (e.g. irritable bowel syndrome, post-bariatric surgery, colorectal carcinoma)
• Metabolic diseases with strong impact on intervention (e.g. type 1 diabetes mellitus, chronic kidney disease)
• Severe food allergies and intolerances, that do not allow adequate implementation of the intervention
• Diagnosed, current psychological comorbidities (bipolar disorder, eating disorder, personality disorder, psychosis)
• intake of antibiotics in the last three months current substance abuse
• Pregnancy and breatfeeding
• Suicidal ideation
• unable to participate or complete questionnaires

Healthy Volunteers:

samples of 32 healthy volunteers are included for microbiome analysis only (

inclusion criteria:

• age ≥ 18 years
• BMI 20 - 30 kg/m^2

exclusion criteria:

• depression or other psychological comorbidities (bipolar disorder, eating disorder, personality disorder, psychosis)

• high adhernece to mediterranean diet: MEDAS ≥ 10

• high adherence to mindful eating: MEI ≥ 5.13

• Diseases of the gastrointestinal tract or metabilic diseases (e.g. irritable bowel syndrome, post-bariatric surgery, colorectal carcinoma, type 1 diabetes mellitus)

  -- intake of antibiotics in the last three months current substance abuse

• pregnancy or breastfeeding

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: FACTORIAL

Arm && Interventions

Group	Intervention	Description
Mediterranean Diet	nutritional intervention	-
Mindful Eating	Mindful Eating	-
Mediterranean Diet and Mindful Eating	nutritional intervention	-
Mediterranean Diet and Mindful Eating	Mindful Eating	-
Befriending	Attention Control	-

Primary Outcome Measures

Name	Time	Method
Depression severity	12 weeks	Beck Depression Inventory - II (BDI-II) scores range from 0 to 63 with higher scores indicating higher depression severity

Secondary Outcome Measures

Name	Time	Method
Depression severity, self assessment	24 weeks	Beck Depression Inventory - II (BDI-II) scores range from 0 to 63 with higher scores indicating higher depression severity
Depression Remission Rates	12 weeks, 24 weeks	rates of participants showing no depressive symptoms, defined as BDI-II less than 9
Quality of Life	12 weeks, 24 weeks	Short Form-36 Health Survey (SF-36), mental and physical sum score, which can be further divided into the subscales vitality, physical functioning, physical pain, general health perception, physical role function, emotional role function, social role function and psychological well-being, higher scores indicate a higher quality of life
Self-efficacy	12 weeks, 24 weeks	general self-efficacy expectation scale, score ranges from 10 to 40, with a higher score indicating a greater expectation of self-efficacy
Health status	12 weeks,	European Quality of Life 5 Dimensions 5 Level (EQ-5D-5L), results in a 5-digit number that describes the patient's health state
Adhernece to Mediterranean Diet	12 weeks, 24 weeks	mediterranean diet adherence score (MEDAS) scores range from 0 to 14 with higher values indicating higher adherence to mediterranean diet
Adherence to Mindfulnes Eating	12 weeks, 24 weeks	Mindfulness Eating Inventory (MEI), score ranges from 1 to 6, with higher scores indicating higher adherence to mindfulness eating
Depression severity, rater assesment	12 weeks	Depresion severity is assessed by psychologists by using the MARDS tool. Scores range from 0 to 60 with higher scores idnicating higher severity of depression
BMI	12 weeks, 24 weeks	weight and height will be combined to report BMI in kg/m\^2
Waist to Hip ratio	12 weeks, 24 weeks	ratio of weight circumference and hip circumference
Body composition: muscle mass	12 weeks, 24 weeks	muscle mass as a percentage of body weight
Body composition: fat mass	12 weeks, 24 weeks	fat mass as a percentage of body weight
adverse events	12 weeks, 24 weeks	time point, duration (in hours or days) and strengths (on a scale from one to ten) of andverse events will be assessed as well as perception of connection between occurrence of adverse event and the intervention
Microbiome Analysis	12 weeks	16s RNA sequencing
cost-utility analysis	12 weeks	from EQ-5D-5L values quality adjustes life years (QUALYS) will be calulated to conduct cost-utility analysis from participants perspective
Qualitative evaluation	12 weeks	Semi-structured interviews will consider two areas: 1. the perception on the intervention in terms of feasibility, difficulties in implementation, perception of study setting, planning of long-term implementation, etc.; 2. perception of effects of interventions, qualitative evaluation of changes in outcoms, i.e. mood, psychological and physical well-being, self-efficacy, etc

Trial Locations

Locations (1)

Robert Bosch Center for Integrative Medicine and Health; 🇩🇪 Stuttgart, Germany