Authors: Muhammad Shahzil, Syeda Kanza Kazmi, Minahel Shehzadi, Fariha Hasan, Mohammad Waqas Danish, Muhammad Saad Faisal, Justin Canakis, Kofi Clarke
Journal: Gastroenterology Research and Practice
Year: 2026
Volume: 2026
Article number: 2994340
DOI: 10.1155/grp/2994340
Study at a glance
- Study type: Systematic review and meta-analysis of randomised controlled trials
- Number of studies: 4 randomised controlled trials
- Participants: 339 patients with inflammatory bowel disease (167 received Mediterranean diet, 172 received non-Mediterranean diets)
- Population studied: Adults and children with ulcerative colitis or Crohn’s disease
- Intervention: Mediterranean diet (high in fruits, vegetables, healthy fats, lean proteins, limited processed foods)
- Comparator: Non-Mediterranean diets (specific carbohydrate diet or regular diet)
- Follow-up duration: 10 to 12 weeks
- Primary outcome(s): Clinical remission (measured using validated disease activity scoring systems), changes in inflammatory markers (C-reactive protein and faecal calprotectin)
Why was this study done?
Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn’s disease, is a chronic digestive condition, which can cause abdominal pain, diarrhoea, bleeding or weight loss, often interfering with daily life.
Diet is thought to play an important role in IBD. The Western diet, high in fats and sugars but low in fruits and vegetables, has been linked to IBD development. Conversely, the Mediterranean diet (rich in plant-based foods, olive oil and fish, with limited red meat and processed foods) has been associated with reduced inflammation.
Shahzil and colleagues conducted this study to evaluate whether the Mediterranean diet improves symptoms in IBD patients compared with other dietary approaches, specifically assessing effects in ulcerative colitis.
How was the study performed?
The researchers searched medical databases up to November 2024 to identify randomised controlled trials comparing the Mediterranean diet with other dietary interventions in IBD patients.
Only trials reporting clinical remission or changes in inflammatory markers (C-reactive protein and faecal calprotectin) were included.
What did the researchers find?
The analysis included four trials with 339 IBD patients: 167 followed the Mediterranean diet, 172 followed non-Mediterranean diets.
Overall, the Mediterranean diet was associated with statistically significant improvement in clinical remission compared with non-Mediterranean diets (risk ratio 1.18, p = 0.02).
When analysing diseases separately, neither showed statistically significant improvements in clinical remission independently. For ulcerative colitis, the risk ratio was 1.15 (p = 0.78); for Crohn’s disease, 1.22 (p = 0.05).
However, when comparing the Mediterranean diet specifically with a regular diet, significant reductions occurred in inflammatory markers: C-reactive protein decreased (mean difference −2.66, p < 0.00001) and faecal calprotectin decreased (mean difference −229.46, p = 0.008).
In ulcerative colitis specifically, the Mediterranean diet significantly decreased both inflammatory markers compared with regular diet.
No significant differences were found between the Mediterranean diet and specific carbohydrate diet in clinical remission or quality of life.
What did the authors conclude?
The authors concluded that the Mediterranean diet shows promise for comprehensive IBD management, offering significant benefits especially in ulcerative colitis through notable reductions in inflammatory markers.
The role in Crohn’s disease regarding clinical remission remains unclear and requires further study.
Future research should identify which patient subgroups benefit most and address adherence challenges. Limitations included small sample sizes and variations in how the Mediterranean diet was defined across trials.
Key takeaways
- The Mediterranean diet was associated with statistically significant overall improvement in clinical remission when all IBD patients were analysed together.
- In ulcerative colitis patients, the Mediterranean diet significantly reduced inflammatory markers when compared with regular diet.
- When analysed separately, neither disease showed statistically significant improvements in clinical remission.
- The Mediterranean diet showed comparable results to the specific carbohydrate diet.
- Larger, longer-term studies with standardised protocols are needed.
This Scientific Publication Summary is an objective summary of the published study for personal and educational use. It does not constitute medical advice, endorsement of the intervention, or a recommendation to alter clinical practice.