Two Healthy Diets Modulate Gut Microbial Community Improving Insulin Sensitivity in a Human Obese Population

Haro, Carmen et al.
[Context] Gut microbiota, which acts collectively as a fully integrated organ in the host metabolism, can be shaped by long-term dietary interventions after a specific diet.
[Objective] The aim was to study the changes in microbiota after 1 year's consumption of a Mediterranean diet (Med diet) or a low-fat, high-complex carbohydrate diet (LFHCC diet) in an obese population.
[Design] Participants were randomized to receive the Med diet (35% fat, 22% monounsaturated) and the LFHCC diet (28% fat, 12% monounsaturated).
[Setting and Participants] The study was conducted in 20 obese patients (men) within the Coronary Diet Intervention With Olive Oil and Cardiovascular Prevention (CORDIOPREV) study, an ongoing prospective, randomized, opened, controlled trial in patients with coronary heart disease.
[Main Outcome Measure] We evaluated the bacterial composition and its relationship with the whole fecal and plasma metabolome.
[Results] The LFHCC diet increased the Prevotella and decreased the Roseburia genera, whereas the Med diet decreased the Prevotella and increased the Roseburia and Oscillospira genera (P = .028, .002, and .016, respectively). The abundance of Parabacteroides distasonis (P = .025) and Faecalibacterium prausnitzii (P = .020) increased after long-term consumption of the Med diet and the LFHCC diet, respectively. The changes in the abundance of 7 of 572 metabolites found in feces, including mainly amino acid, peptide, and sphingolipid metabolism, could be linked to the changes in the gut microbiota.
[Conclusions] Our results suggest that long-term consumption of the Med and LFHCC diets exerts a protective effect on the development of type 2 diabetes by different specific changes in the gut microbiota, increasing the abundance of the Roseburia genus and F. prausnitzii, respectively.
The CORDIOPREV study is supported by the Fundación Patrimonio Comunal Olivarero, Junta de Andalucía (Consejería de Salud, Consejería de Agricultura y Pesca, Consejería de Innovación, and Ciencia y Empresa), Diputaciones de Jaén y Córdoba, Centro de Excelencia en Investigación sobre Aceite de Oliva y Salud and Ministerio de Medio Ambiente, Medio Rural y Marino, and Gobierno de España. In addition, it was partly supported by research grants from the Ministerio de Ciencia e Innovación (AGL2009–122270 to J.L.-M., FIS PI10/01041 to P.P.-M., and PI10/02412 to F.P.-J.), Ministerio de Economia y Competitividad (AGL2012/39615, PIE14/00005, and PIE14/00031 to J.L.-M.; PI13/00619 to F.P.-J.), Consejería de Economía, Innovación y Ciencia, Proyectos de Investigación de Excelencia, Junta de Andalucía (AGR922 to F.P.-J.), Consejería de Salud, Junta de Andalucía (PI0193/09 to J.L.-M., PI-0252/09 to J.D.-L., and PI-0058/10 to P.P.-M.), Consejería de Innovación Ciencia y Empresa (CVI-7450 to J.L.-M.), and Fondo Europeo de Desarrollo Regional. A.C. is supported by an Instituto de Salud Carlos III research contract (Programa Miguel-Servet CP14/00114). J.F.A.-D. is supported by an Instituto de Salud Carlos III research contract (Programa Rio-Hortega).