Diet-Dependent Microbial and Metabolic Signatures in Food: Implications for Cardiovascular Health

Each meal introduces billions of mostly harmless bacteria. Food-associated microbes and their metabolites can influence disease prevention and treatment. This study presents integrative profiling of food as a novel approach for monitoring cardiovascular diseases (CVDs). To explore dietary impacts on cardiovascular health, a randomized, cross-over controlled clinical trial was conducted at Imperial College London. Hospitalized participants followed two 3-day dietary interventions: one healthy (HD: high fibers, low fats) and one non-healthy (NHD: low fibers, high fats). Composite diet samples were analyzed via 16S rRNA sequencing at the University of Milano-Bicocca, generating 8,864,768 reads. Alpha diversity was higher in NHD (464 vs 103 genera), based on Pielou and Shannon indexes. Beta diversity also differed significantly (Bray-Curtis, Jaccard). HD was dominated (relative abundance >3%) by Janthinobacterium, Serratia, and Flavobacterium, while NHD diet featured Bacillus, Photobacterium, Thermus, Anoxybacillus, and Geobacillus. Pseudomonas and Lactococcus were prevalent in both. Over 50 genera differed significantly between diets, with ASVs from the same genus often showing opposing trends. Metabolic profiling (PLS-DA) revealed 39 significantly different metabolites, including SCFAs. Acetate was associated with 7 genera in HD; propionate was positively associated with Paraburkholderia and negatively with Romboutsia. In NHD, 9 genera were negatively correlated with propionate and 38 with acetate. These findings highlight the value of examining both microbial and metabolic composition, particularly SCFAs, in assessing dietary health effects. The diet-dependent microbial and metabolic signatures suggest a potential mechanism linking diet to CVD risk, supporting the development of microbiome-informed nutritional strategies for CVD prevention and management.