Litesse polydextrose, a low calorie, low glycaemic carbohydrate, may increase Bifidobacterium and Allobaculum—bacteria linked to lean phenotype and improved lipid metabolism—in the gastrointestinal tracts of mice.
Polydextrose’s effect on beneficial bacteria numbers, reduction in triglyceride and total cholesterol levels in addition to fat mass, is also supported by the fibre’s enhanced satiety effect.
The authors of the study, in which mice were fed a modern diet rich in high fat/high density food, believe it is this quality that could aid in decreasing food intake amongst the Western population.
“While this study was conducted on mice, some human results are in line with what we discovered, although in humans the mechanisms are not yet as clear,” said Professor Karl-Heinz Herzig, co-lead investigator from the University of Oulu in Finland.
“These results are very encouraging and should be followed up in human trials.”
Litesse polydextrose is only partially fermented by the gut microbiota, contributing to only one calorie (cal) per gram (g) to food and beverage products compared to sugar (4 cal/g) and fat (9 cal/g).
As a prebiotic fibre, previous work has seen positive effects from doses as low as 4 g/day in humans.
Along with fellow lead investigator Ghulam Raza, Professor Herzig gave six mice 75 milligrams (mg) of Litesse polydextrose twice daily for 14 days.
Body weight and food intake were monitored daily. Fasting plasma lipids, caecal microbiota and gene expression in intestine and liver were also measured after 14 days of feeding.
The researchers found that polydextrose supplementation significantly reduced food intake, fasting plasma triglyceride and total cholesterol.
Microbiome analysis revealed that the relative abundance of Allobaculum, Bifidobacterium and Coriobacteriaceae taxa associated with lean phenotype, increased in mice on a western diet supplemented with polydextrose.
Gene analysis showed consistent downregulation of Dgat1, Cd36, Fiaf and upregulation of Fxr in duodenum, jejunum, ileum and colon in these mice.
“These results suggest that polydextrose in mice following a Western diet promoted systemic changes via regulation of the gut microbiota and gene expression in intestinal tract,” the study concluded.
“It is very plausible that polydextrose supplementation and its fermentation in colon could affect the lipid metabolism in liver through gene expression regulation, even though we observed only trends between the gene expression and plasma lipid values.”
The stomach to compete for business
The benefits of prebiotic fibres have not been lost on health food manufacturers eager to ride the wave of gut health knowledge and its strong links to neurological function and conditions.
Beneo’s Orafti inulin and oliogofructose are perhaps the best known. With these two ingredients manufacturers can claim a 13.5 European health label for improved blood glucose management. Orafti Inulin allows two 13.5 European health claims on the product packaging: "promotes digestive health" and "lowers blood glucose rise".
Meanwhile, UK-based Optibiotix, involved in the modulation of the human microbiome, are developing a range of naturally sweet prebiotic fibres, called SweetBiotix, which are not digested in the human gut, and hence calorie free.
Other prebiotic fibre ingredients include Nutriose from Roquette, Tereos’ Actilight fibre, Olygose’s oligosaccharide and chicory root fibres produced by Sensus and Cosucra-Group Warcoing.
Source: Nature Scientific Reports
Published online ahead of print: doi:10.1038/s41598-017-05259-3
“Polydextrose changes the gut microbiome and attenuates fasting triglyceride and cholesterol levels in Western diet fed mice.”
Authors: Karl-Heinz Herzig et al.