Project results: Understanding the role of diet on gut microbiota to reduce cardiometabolic disease risk

The human intestinal microbiome plays a crucial role in our health. Variations in gut microbiota and decreased microbial diversity have been shown to increase the prevalence of non-communicable diseases. Diet can have a strong modulating effect on microbiome composition, directly influencing the incidence of metabolic diseases. However, the effect of diet on gut microbiota strongly varies per individual. Understanding the underlying mechanisms of diet – microbiota interactions provides a foundation for tailored dietary strategies for personalized precision nutrition to reduce the risk of cardiometabolic diseases.

Researchers from Sweden, Spain, Italy and Denmark collaborated on the project ‘Diet x gut microbiome-based metabotypes to determine cardiometabolic risk and tailor intervention strategies for improved health’ (DiGuMet). The project ran between 2018-2022. The aim was to investigate how gut microbiota interact with diet and to identify the role of these interactions on cardiometabolic risk factors. The project was cofunded by the European Commission within the HDHL-INTIMIC cofunded call.

Aim

The DiGuMet project aimed to explore how gut microbiota interact with diet and the role of such interactions for cardiometabolic disease risk and to dissect underlying mechanisms and finding biomarkers reflecting such interactions, through extensive molecular phenotyping e.g., microbiomics and metabolomics combined with lifestyle data. The project used large scale observational data and intervention data to explore how changes in diet are associated with gut microbiota and derived metabolites, and to find groups of individuals belonging to different metabotypes. Metabotypes are groups of individuals with a similar metabolic phenotype (set of metabolites). Each metabotype has a unique response to the same foods. The metabotype approach helps to understand individual responses to interventions, and to ultimately offer guidance for personalized nutrition.

The DiGuMet hypothesis was that gut microbiota - diet interactions are a major determinant of the metabotypes and that distinct metabotypes could be reflected by predictive biomarkers. These biomarkers could then be used to tailor personalised dietary interventions to improve the molecular phenotypes among subjects at elevated risk of cardio vascular diseases. The hypothesis was tested by conducting a dietary intervention rich in fermentable vs non-fermentable cereal fibres among subjects with signs of metabolic syndrome with distinct differences in their pattern of microbiota and microbiota-derived metabolites.

Vlog contest

As part of the JPI HDHL conference in 2019, a science vlog (video log) contest for early career scientists was organised. An early career scientist of the DiGuMet project participated in the contest. Watch the vlog here.

Results

The study found that fermentable fibres, provided as part of newly developed foods in the DiGuMet project, increased postprandial (after meal) short-chain fatty acids (SCFA) in individuals with high risk of cardiometabolic disease, suggesting a favourable effect in terms of cardiometabolic disease risk. SCFAs are produced through the fermentation of dietary fibres by gut microbiota, and they are associated with beneficial effects on cardiometabolic risk factors.

The project developed 3 dietary fibre enriched foods that can be used as challenge tests in order to determine SCFA responders and non-responders, i.e. butyrogenic and propiongenic metabotypes and the identification of differential effects on cardiometabolic risk factors including plasma glucose, insulin, blood lipids and free fatty acids. The fermentable fiber challenge test, which was developed in this study, is now being optimized and validated in external studies and is expected to ultimately contribute to prevision nutrition strategies to prevent cardiometabolic disease for groups or individuals.

Additionally, the project found that postprandial metabotypes were more evident and straightforward to detect than multi-omics based metabotypes in the free-living population.

Based on these two main findings, the consortium expanded on existing databases and developed new methods, tools and software, which will contribute enormously to subsequent research and the development of evidence based recommendations and novel food products.

In total, 11 projects were funded within the HDHL-INTIMIC cofunded call. All results will be shared on our website. Stay tuned! See ‘more information’ below for already published project results.

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