Mediterranean-Like Dietary Pattern Associations With Gut Microbiome Composition and Subclinical Gastrointestinal...

Area of Science:

• Gastroenterology
• Microbiome Research
• Nutritional Science

Background:

• Crohn's disease (CD) patients exhibit altered gut microbial composition compared to healthy individuals.
• Epidemiological studies suggest diet significantly contributes to CD risk by modulating gut bacteria and inflammation.
• The precise relationship between long-term dietary patterns, gut microbiome, and subclinical inflammation remains to be fully elucidated.

Purpose of the Study:

• To identify distinct dietary patterns within a cohort of healthy first-degree relatives (FDRs) of CD patients.
• To investigate the association between these identified dietary patterns and specific gut microbial compositions.
• To assess the relationship between dietary patterns, gut microbiome, and subclinical gut inflammation markers.

Main Methods:

• Recruited 2289 healthy FDRs of CD patients for the Genetic, Environmental, Microbial (GEM) Project.
• Collected stool samples and utilized validated food frequency questionnaires to assess habitual diet over the preceding year.
• Employed unsupervised analysis to identify distinct dietary clusters (DCs) and microbial composition clusters.

Main Results:

• A Mediterranean-like dietary pattern (DC3) was strongly associated with a specific microbial composition, including increased fiber-degrading bacteria (e.g., Ruminococcus) and Faecalibacterium.
• The DC3 dietary pattern showed a significant association with lower levels of subclinical gut inflammation, as measured by fecal calprotectin.
• Mediation analysis revealed that the Mediterranean-like diet had a direct effect on reducing inflammation, partially mediated by the gut microbiota.

Conclusions:

• Mediterranean-like dietary patterns are associated with a favorable gut microbiome composition and reduced intestinal inflammation.
• Long-term dietary patterns, rather than individual foods, appear to influence subclinical gut inflammation.
• Findings support the development of targeted dietary strategies to modulate the microbiome and reduce gut inflammation for disease prevention.