Inflammatory Bowel Disease (IBD), Ulcerative Colitis (Disorder)
Conditions
Keywords
Mediterranean Diet, Short-Chain Fatty Acids, Dietary Intervention, Time-Restricted Feeding, Ulcerative Colitis, Inflammation
Brief summary
This study will evaluate whether a 12-week dietary intervention can improve gut health, inflammation, and quality of life in adults with ulcerative colitis in remission. Participants will be randomly assigned to one of three groups: a Mediterranean diet, a Mediterranean diet combined with time-restricted feeding (eating within an 8-hour window each day), or standard dietary advice. The Mediterranean diet emphasizes fruits, vegetables, whole grains, legumes, nuts, olive oil, and fish, while limiting processed foods and red meat. The main outcome will be changes in short-chain fatty acids in stool samples, which are markers of gut health. Additional outcomes include changes in inflammation markers, gastrointestinal symptoms, and quality of life. The results of this study may help identify effective dietary strategies to support patients with ulcerative colitis.
Detailed description
Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by periods of remission and relapse, associated with alterations in the gut microbiota, immune dysregulation, and impaired intestinal barrier function. Current treatments focus on controlling inflammation; however, there is a growing interest in non-pharmacological strategies, including dietary interventions, to improve disease outcomes and quality of life. The Mediterranean diet has been associated with anti-inflammatory effects, improved gut microbiota composition, and increased production of short-chain fatty acids (SCFAs), which play a key role in maintaining intestinal homeostasis. Time-restricted feeding (TRF), a form of intermittent fasting that limits daily food intake to a specific time window, has shown potential metabolic and anti-inflammatory benefits in preclinical and human studies. However, evidence on the combined effects of these interventions in patients with UC is limited. This study is a pilot randomized controlled trial designed to evaluate the effects of a 12-week intervention with a Mediterranean diet alone or in combination with TRF on gut health, inflammation, and quality of life in patients with UC in remission. A total of 45 participants will be randomized in a 1:1:1 ratio into three groups: (1) Mediterranean diet, (2) Mediterranean diet combined with TRF (16-hour fasting and 8-hour eating window), and (3) standard dietary advice (control group). Nutritional plans will be individualized and isocaloric. Participants will be assessed at baseline, week 6, and week 12. The primary outcome is the change in fecal SCFA levels, measured using gas chromatography. Secondary outcomes include changes in fecal calprotectin, C-reactive protein, gastrointestinal symptoms, and quality of life assessed by validated questionnaires. This study aims to generate preliminary evidence on the effectiveness and feasibility of combined dietary interventions in UC, supporting future larger-scale clinical trials.
Interventions
BEHAVIORALMediterranean Diet
Participants will receive individualized nutritional counseling to follow a Mediterranean diet, emphasizing high intake of fruits, vegetables, whole grains, legumes, nuts, olive oil, and fish, and reduced consumption of red meat and ultra-processed foods. Dietary plans will be tailored to individual energy requirements.
BEHAVIORALMediterranean Diet + Time-Restricted Feeding
Participants will follow a time-restricted feeding protocol (16:8), consisting of a daily 16-hour fasting period and an 8-hour eating window (12:00-20:00). During the eating window, participants will consume meals based on Mediterranean diet guidelines, with individualized dietary counseling to ensure adequate nutritional intake.
BEHAVIORALStandard Dietary Advice
Participants will receive standard dietary counseling based on current clinical guidelines for ulcerative colitis. This includes general recommendations for a balanced diet without specific emphasis on Mediterranean dietary patterns or time-restricted feeding.
Sponsors
Pontificia Universidad Catolica de Chile
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Participants will be randomly assigned in a 1:1:1 ratio to one of three parallel groups: Mediterranean diet, Mediterranean diet combined with time-restricted feeding (16:8), or standard dietary advice (control). Each participant will remain in their assigned group for the entire 12-week intervention period.
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
No
Inclusion criteria
* Adults aged 18 to 60 years * Diagnosis of ulcerative colitis * Clinical remission for at least 6 months * Fecal calprotectin \< 250 µg/g in the last 3 months * Daily eating window ≥ 11 hours
Exclusion criteria
* Active ulcerative colitis * History of gastrointestinal surgery * Liver or kidney disease * Pregnancy * Eating disorders * Use of supplements (protein, antioxidants, probiotics) * Current restrictive diets (vegetarian, vegan, gluten-free, low-FODMAP) * High levels of physical activity
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in fecal short-chain fatty acid (SCFA) levels | Baseline to 12 weeks | Fecal SCFA concentrations will be measured using gas chromatography and expressed as total and individual SCFA levels. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in fecal calprotectin | Baseline to 12 weeks | Fecal calprotectin levels will be measured as a marker of intestinal inflammation. |
Countries
Chile
Contacts
CONTACTAlejandra Parada Daza, Phd
Outcome results
None listed