European study coordinated by the University of Naples Federico II
Beneficial effects of the Mediterranean Diet in overweight and obese subjects. Li demonstrates a European study, coordinated by the University of Naples Federico II, in collaboration with the University of Copenhagen and the French institute MetaGenoPolis.
Beneficial effects of a nutritional intervention with the Mediterranean Diet on the composition and functions of the intestinal microbiome, on the systemic metabolome and on cholesterol levels in an overweight population at risk of developing cardiovascular diseases. Li demonstrates a European study, coordinated by the University of Naples Federico II, in collaboration with the University of Copenhagen and the French institute MetaGenoPolis.
The research, just published in the prestigious scientific journal Gut, shows that there is a direct relationship between nutrition, the intestinal microbiome and human health.
The partners of the DINAMIC European project - Diet-induced Arrangement of the gut Microbiome for Improvement of Cardiometabolic health - conducted an 8-week randomized controlled nutritional intervention study in overweight and obese subjects with a sedentary lifestyle. The results clearly show that a change in eating behavior, without any concomitant modification of the individual energy intake of macronutrient intake and physical activity, can reduce blood cholesterol levels, already after 4 weeks, in a high-risk population cardio-metabolic for an incorrect lifestyle. Furthermore, greater adherence to the Mediterranean diet induces changes in the intestinal microbiome and its functionality, which are important for human health. In line with aspects related to personalized nutrition, the data show that some individuals host an intestinal microbiome that is more susceptible to changes induced by the Mediterranean diet and face further clinical advantages such as the improvement of insulin sensitivity and inflammatory status.
The multidisciplinary team saw the research groups of teachers Danilo Ercolini, Paola Vitaglione and Angela Rivellese from the Federico II Task Force for Studies on the Microbiome as protagonists; Lars O. Dragsted and Henrik M. Roager of the Department of Nutrition, Exercise and Sport of the University of Copenhagen, and members of the research group of the French research institute MetaGenoPolis (INRAE) of the University of Paris-Saclay coordinated by Dusko S Ehrlich.
Therefore, we analyzed the effect of the Mediterranean diet on the composition of the intestinal microbiome and on clinical, metabolic and anthropometric parameters of 82 healthy, overweight and obese subjects, at risk of developing cardiovascular diseases. Participants were included in the intervention group with Mediterranean diet (n = 43) or in the control group (n = 39). The participants in the Mediterranean diet group received an individual diet plan based on the Mediterranean model, equivalent to the usual one for calories and macronutrient composition. So these volunteers increased the intake of dietary fiber, vegetable proteins and unsaturated fats and reduced simple carbohydrates, animal proteins and saturated fats. The volunteers in the control group did not change their eating habits for the duration of the study. All volunteers maintained the sedentary lifestyle during the intervention period.
From the analysis of metagenomics data, analysis of the genomes of all the components of the intestinal microbiome, and metabolomics, analysis of metabolites, the profile of the microbiome and metabolome of the population under study was defined together with the clinical and anthropometric data.
After 4 weeks the volunteers who consumed a Mediterranean diet showed a reduction in total plasma cholesterol compared to the controls. In addition, the volunteers who increased the adherence to MD more also showed an increase in the fibers that degrade the fibers and that produce short chain fatty acids, such as some strains of Faecalibacterium prausnitzii, an enrichment in the degradation pathways of metabolism triglycerides butyrate and a decrease in potentially pro-inflammatory species, e.g. Ruminococcus gnavus. Adherence to the Mediterranean diet has been demonstrated with an increase in the markers of consumption of foods of vegetable origin and a decrease in those of foods of animal origin such as lower plasma and urinary levels of carnitine and degradation products of animal proteins. As regards the microbial metabolites of healthy interest and linked to the diet, an increase in the levels of urolithins has been shown in the urine, molecules with anti-inflammatory properties produced by the intestinal microbiota starting from polyphenols present in walnuts. Finally, a decrease in faecal bile acid production and insulin resistance was observed, and these changes were related to basal levels and changes in the microbial species involved in these specific metabolic characteristics.