Dietary fiber-microbiota: novel mechanisms for metabolic control
Impacting microbiota through fiber intake
A recent report appearing in the journal Science (Zhang et al., 2018) shows one novel mechanism by which dietary fiber could enhance metabolic health. The researchers, working with patients with type 2 diabetes mellitus, caused by insulin resistance, show that fiber intake improves glucose metabolism, by reducing HbA1c values. This marker was improved in near of 90% participants receiving a mixture of dietary fibers derived from vegetables, in addition to conventional dietary treatments. Furthermore, dietary fiber impacts blood lipid profile and improves body weight in these volunteers. This has been previously linked to changes in production of the so-called incretins (i.e. hormones produced by gut that impact on pancreatic function, improving insulin secretion). Among other molecules, these incretins comprise GLP-1 and PYY, which were increased in the volunteers with the fiber intake. Nonetheless, the authors also showed that dietary fiber intake changed microbiota, leading to increased production of short chain fatty acids, such as butyrate and other metabolites, such as indole. Interestingly, these changes in colonic microbiota could be transferred to experimental mice.
Importantly, Fibracep® is a mixture of vegetable fibers, with demonstrated effects over similar indexes, both in preclinical models of obesity (i.e. in mice) and in humans at risk of metabolic syndrome. Our data demonstrate that volunteers with Fibracep® intake change the levels of short chain fatty acid levels in colon, simulating the results published in Science. Thus, evaluation of volunteers before taking Fibracep® reveal profound changes in microbiota among individuals with hypercholesterolemia (Granado-Serrano et al., 2017). Ongoing analyses show that Fibracep® intake, in addition to changes in short chain fatty acid levels, is also able to modulate incretin production, a differential fact that other soluble or insoluble fibers do not show.
L. Zhao, F. Zhang, X. Ding, et al. Gut bacteria selectively promoted by dietary fibers alleviate type 2 diabetes. Science, 359 (2018), pp. 1151-1156
Granado-Serrano A, Marti-Gari M et al. Fecal microbiota characterization of hypercholesterolemic subjects. Proceedings of the BARCELONA DEBATES ON THE HUMAN MICROBIOME 2017 FROM MICROBES TO MEDICINES (https://www.bdebate.org/sites/default/files/bdebate_microbiome_program_final.pdf)