Impact of a Short-Term Mediterranean-Style Diet on Health Indices (MEDWELL)

Exploring the Effects of a Short-term Mediterranean-style Dietary Intervention on Indices of Mood and Wellbeing in UK Adults

Emerging evidence suggests protective properties of a Mediterranean diet (MD) in relation to prevention and management of mood disorders. However, there is paucity of dietary interventions investigating adherence to MD and effects on mood and wellbeing in individuals without a clinical diagnosis. The present study aimed to investigate the effects of adherence to a short-term MD on mood and wellbeing in healthy adults

Study Overview

• Status: Completed
• Conditions: Healthy
• Intervention / Treatment: Other: A mediterranean style diet; Other: Habitual Diet

Detailed Description

This is a 1-week, cross-over, randomised, controlled study investigating the effects of Mediterranean style diet on perceived mood and overall wellbeing in healthy adults. The intervention consists following daily for 1 week a Mediterranean style eating pattern. Participants are following their habitual diet during the control week. This is an investigator-initiated, randomised, cross-over, controlled study.

• Study Type: Interventional
• Enrollment (Actual): 22
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United Kingdom
  • UK
    • London, UK, United Kingdom, SW15 4JD
      • University of Roehampton, School of Life and Health Sciences

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Habitual diet of low Mediterranean Diet (MD)adherence i.e. individuals with MD scoring ≤7 (low adherence) were included.
• Living in UK

Exclusion Criteria:

• pregnant or breastfeeding following a weight loss diet
• diagnosed medical condition (diabetes, cardiovascular disease, cancer, food allergies)
• have any further health conditions which may cause you to react adversely whilst changing your diet.
• diagnosed with a neurological impairment or psychiatric disorder
• Current smoker (last 12 months)
• history of substance abuse
• taking dietary supplements
• already following a Mediterranean style diet

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: A Mediterranean style diet; At baseline, participants attended an Educational Group Session (EGS) introducing the principles of the Mediterranean Diet (MD), including recommended foods, foods to limit, cooking methods, and shopping tips. Participants then followed a Mediterranean-style diet for 7 days, replacing typical Western foods with MD alternatives without restricting energy intake. Practical examples and take-home materials with simple food swaps were provided to support adherence.	Other: A mediterranean style diet; At baseline, an Educational Group Session (EGS) introduced participants to the Mediterranean Diet (MD) principles to support adherence. The interactive EGS covered MD typical foods to consume and avoid, cooking methods, and practical shopping guidance. Following the EGS, participants adopted a Mediterranean-style diet for a period of 7 days. Participants were encouraged to follow the MD guidelines (replacing typical western foods with MD foods) without restricting energy intake; examples were provided during the EGS and with take-home resource materials which detailed 'simple swaps' or alternative MD food items to replace western food items.; Other Names: MD
Placebo Comparator: Habitual diet; Participants were instructed to follow their habitual diet (control) and eating practices for 7 days. without restricting energy intake.	Other: Habitual Diet; participants were instructed to follow their habitual diet (control) and eating practices for 7 days. without restricting energy intake.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mood	Change in mood measured using the Bond-Lader Visual Analogue Scale (VAS). The scale ranges from 0 to 100, with higher scores indicating a more positive mood state (better outcome).	Baseline and 7 days (final day of each condition) espressed in questionnaire scores

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Wellbeing	Change in wellbeing measured using the Warwick-Edinburgh Mental Wellbeing Scale (WEMWBS). The WEMWBS total score ranges from 14 to 70, with higher scores indicating greater mental wellbeing (better outcome).	Baseline and 7 days (final day of each condition) espressed in questionnaire scores

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Body weight	Change in body weight, measured in kilograms (kg) Change in waist circumference, measured in centimetres (cm). Lower waist circumference indicates a better outcome where reduction in central adiposity is a study objective.	Baseline and 7 days (final day of each condition) expressed in Kg
Physical activity	Change in physical activity measured using the International Physical Activity Questionnaire (IPAQ), expressed as total metabolic equivalent (MET)-minutes per week. Higher scores indicate greater physical activity levels (better outcome). The IPAQ does not have a fixed minimum or maximum score.	Baseline and 7 days (final day of each condition) espressed in questionnaire scores
Dietary intake	Change in dietary intake assessed using 7-day weighted food records collected during each 7-day intervention period. Dietary intake was quantified as daily energy and nutrient intake. There is no fixed minimum or maximum score; values are reported in their respective units (e.g., kcal/day, g/day). The direction of a better outcome depends on the specific dietary component being evaluated.	During the 7 days intervention/condition using DietPlan software

Collaborators and Investigators

• Sponsor: University of Roehampton
• Investigators: Principal Investigator: Fotini Tsofliou, University of Roehampton

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2019
• Primary Completion (Actual): May 12, 2019
• Study Completion (Actual): August 20, 2019

Study Registration Dates

• First Submitted: June 19, 2026
• First Submitted That Met QC Criteria: July 15, 2026
• First Posted (Actual): July 16, 2026

Study Record Updates

• Last Update Posted (Actual): July 16, 2026
• Last Update Submitted That Met QC Criteria: July 15, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: MED-MOOD-UK-2026-001

Drug and device information, study documents

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