Fiber Consumption Increases Beneficial Bacteria in the Gut Microbiome
8/20/2015 9:43:25 AM
In a study published in the American Journal of Clinical Nutrition, researchers investigated the impact of dietary fiber supplementation on the fecal microbiome of healthy adults. Performed at the University of Illinois, the study is the first to examine how supplementation with 2 different forms of dietary fiber affects the function of the fecal microbiome and how the gut’s microorganisms evolve.
The study was a double-blind, placebo-controlled, crossover trial performed on 21 healthy adult men who were randomized into 3 groups for 3 weeks: group 1 consumed supplement bars that contained no fiber, group 2 consumed bars containing the synthetic glucose polymer polydextrose (21 g/d), and group 3 ate bars containing soluble corn fiber (21 g/d).
After fecal specimens were collected from each participant, researchers tested specimen DNA via whole-genome shotgun 454 pyrosequencing, which reported a snapshot of all the bacterial genetic information in the fecal microbiome. The research team sought this information to understand more about how bacteria in the gut function when fiber is part of a regular diet. They found that fiber supplementation increased the numbers of beneficial bacteria, which ultimately aided digestion in those participants who ingested added fiber.
Researchers estimate that only 10% of the American population consumes enough fiber for to maintain a healthy gastrointestinal system (25 g-38 g/d), so thanks to this study, practitioners now have even more reason to encourage fiber consumption as an aid to weight loss and disease prevention.
Source: Holscher HD, Caporaso JG, Hooda S, Brulc JM, Fahey GC Jr, Swanson KS. Fiber supplementation influences phylogenetic structure and functional capacity of the human intestinal microbiome: follow-up of a randomized controlled trial. Am J Clin Nutr. 2015;101(1):55-64. Epub 2014 Nov 12.