June 18, 2025
3 min read
Key takeaways:
- Adherence to a Mediterranean diet was linked to a noncomplicated Crohn’s disease course.
- It also was associated with reduced inflammation and improved microbial and metabolite composition.
Adherence to a Mediterranean diet appeared associated with beneficial clinical outcomes and reduced inflammatory markers among patients with newly diagnosed Crohn’s disease, according to study results published in Gastroenterology.
These effects may be linked to shifts in microbial and metabolite composition, researchers noted.
“Diet matters — and dietitians should be an integral part of the multidisciplinary care team in IBD,” Lihi Godny, RD, PhD, research dietitian in the division of gastroenterology at Rabin Medical Center in Israel, told Healio. “While many exclusion diets are available for Crohn’s disease, the Mediterranean diet offers an inclusive and sustainable alternative that emphasizes diversity of unprocessed, plant-based foods. Our findings highlight its potential to shape microbial composition, reduce inflammation and support a more favorable disease course.”
The Mediterranean diet has been associated with positive outcomes, including reduced disease activity, lower inflammatory markers and improved quality of life, among patients with inflammatory bowel disease, according to study background. Its effect on newly diagnosed CD is not well understood.
Godny and colleagues investigated this in a prospective, longitudinal observational study of adult patients with newly diagnosed CD, who were managed and followed by a multidisciplinary care team from 2013 to 2024. Participants received disease-specific, Mediterranean diet-based recommendations from IBD dietitians and follow-up visits for nutritional support as needed.
Researchers tracked dietary adherence through a series of food frequency questionnaires and a novel, microbiota-targeted Mediterranean diet-based adherence screener, which provided scores based on high or low consumption of recommended dietary components.
They also evaluated Crohn’s disease activity index (CDAI), C-reactive protein and fecal calprotectin, as well as fecal samples for microbial and metabolomic composition.
The researchers recruited 271 consecutive patients (median age, 27 years; interquartile range, 22-38; 52% men; inflammatory B1 phenotype, 76%) and collected a total of 636 food frequency questionnaires (range, 1-5 questionnaires per patient).
Just over half (51%) of patients had a complicated disease course throughout follow-up, which included IBD-related hospitalizations or surgery, use of at least two biologics in a year or development of complex perianal disease.
Results showed higher Mediterranean diet adherence among those with noncomplicated vs. complicated disease.
Overall, higher adherence scores were inversely associated with CDAI, CRP, fecal calprotectin and microbial dysbiosis (all P < .05).
High adherence also was associated beneficial microbial groups such as Faecalibacterium, whereas low adherence was linked to inflammatory groups, including Escherichia coli and Ruminococcus gnavus.
“When exploring diet-microbiota interactions, we observed that higher adherence to the Mediterranean diet — and greater intake of its core components such as fruits, vegetables, legumes, seeds and a greater diversity of plant colors — was positively associated with a beneficial microbial cluster enriched in commensals and short-chain fatty acid producers,” Godny said. “In contrast, it was inversely associated with a microbial cluster dominated by pathobionts and specific metabolites hypothesized to promote intestinal inflammation.”
Researchers acknowledged study limitations, including its observational design, which did not allow for causal inference, and small sample size.
“It is possible that patients with a milder or noncomplicated disease course found it easier to adhere to the Mediterranean diet, rather than the diet itself being the driver of improved outcomes,” Godny said. “Additionally, the modest sample size may limit the generalizability of the findings to broader and more diverse populations. To address these limitations, further intervention studies are needed.”
Ongoing research in the Division of Gastroenterology at the Rabin Medical Center, Israel, led by Iris Dotan, MD, includes global trials involving cultural adaptations of the Mediterranean diet to meet the needs of diverse dietary practices and populations, she said.
“In these studies we aim to identify which patients are most likely to benefit from the Mediterranean diet or specific components of it, supporting the development of more personalized and targeted dietary strategies in IBD care,” she added.
According to Godny, this study’s findings show that the Mediterranean diet, when incorporated into routine care through dietary counseling, may improve disease management and outcomes and benefit gut health.
“Importantly, in most patients, the Mediterranean diet should be considered as an adjunct to — not a replacement for — medical therapy,” she said. “Personalization is essential, and dietitians play a key role in tailoring the diet to individual needs and ensuring long-term adherence.”
For more information:
Lihi Godny, RD, PhD, can be reached at gastroenterology@healio.com.