Gut bacteria ‘shift’ from fibre could aid weight loss

Dietary fibre can cause a shift in the gut toward beneficial bacteria may have the potential to assist in weight loss, while also reducing the risk of colon cancer, type 2 diabetes, and other diseases, say researchers.

New research from the USA has suggested that supplementation with two specific functional fibres may also have the potential to assist in weight loss when made part of a long-term, daily diet.

Published in the American Journal of Clinical Nutrition, the new data uses genomic sequencing techniques to fully explore the changes in microbiota seen in a previous clinical trial – which suggested that fibre supplementation decreased faecal putrefaction compounds and shifted the abundances of several bacterial taxa.

The team team had previously been able see a ‘snapshot’ of what bacteria were present in the gut after the clinical trial in which diets were with polydextrose and soluble corn fiber. Now, using the samples from the same trial, the team used whole-genome sequencing to explore the full range of bacterial genomic information in the gut after fibre supplementation.

“This study conveys novel information about the impact of dietary fibre supplementation on the phylogenetic structure and functional capacity of the faecal microbiome of healthy adults,” wrote the team – led by Kelly Swanson from the University of Illinois. 

Indeed, Swanson and his colleagues noted that one of the most surprising and novel findings from the more in depth analysis was a shift in the Bacteroidetes:Firmicutes ratio toward more Bacteroidetes - something the researchers had not seen previously.

"This was of particular interest to us because other research has shown that having more Bacteroidetes may be beneficial because the higher that proportion is, the individual tends to be leaner,” noted Hannah Holscher – first author of the paper. “With higher Firmicutes, that individual tends to be more obese.”

"We don't know if there is any causality for weight loss, but studies have shown that having a higher fibre diet is protective against obesity. It's an exciting shift and helps to drive researchers to study these fibres as part of a weight loss diet,” she added.