“Although {inulin-type fructans} supplementation does not influence serum markers of inflammation, our results suggest that it decreases local gut inflammation, an effect which could be interesting in patients presenting co-morbidities like diverticulosis associated with overweight or obesity,” the authors wrote.
“It is interesting that the statistical drop in one species of Erysipelotrichaceae in the prebiotic group was associated with lowered calprotectin. Erysipelotrichaceae, belongs to the Firmicutes phylum and was correlated with gastrointestinal tract inflammation in patients with colorectal cancer or inflammatory bowel disease.”
“This is a well-conducted study that has up-to-date methodologies,” said Glenn Gibson who is a Professor of Food Microbiology and head of Food Microbial Sciences at the University of Reading in the UK and a world-renowned expert in pre and probiotics. “Prebiotics should be selective in their fermentative microbial metabolism and as a result impart health-promoting properties. This is the case here, with a well-researched prebiotic, albeit that the observations are not particularly novel. A lack of response in SCFA does not surprise me given that feces represents only a small fraction of those produced.”
The research team also noted that the majority of SCFA, up to 85%, are rapidly absorbed by cells lining the colon, “resulting in decreasing concentrations from the proximal to distal colon. Therefore, only a minor fraction of SCFA, about 5%, is excreted in faeces. Thus, we cannot conclude that the higher SCFA level strictly reflects SCFA production by the gut microbiota.”
For this study data from a small sub-cohort of obese patients in the Food4Gut randomized placebo-controlled trial was examined and analyzed who received either 16 grams per day of inulin or a maltodextrin placebo. All participants received dietary advice and were asked to restrict caloric intake, resulting in lower energy and protein intakes.
In the inulin group levels of Bifidobacterium substantially increased, this was supported by data from a larger cohort, and the researchers reported a 50% decrease in fecal calprotectin after three months of supplementation.
The authors wrote, “… the drop in fecal calprotectin observed after prebiotic intake emphasizes the potential interest of prebiotic intake to combat gut inflammatory disorders occurring with obesity, an effect that could be related to changes in the abundance of bacteria like Erysipelotrichaceae.”
Based on their findings the researchers concluded that; “If the increase in Bifidobacterium appears as a reproducible signature of inulin intake in the whole cohort of obese individuals, other bacteria or bacterial co-metabolites(like rumenic acid) could be implicated in ITF interaction with the gut microbiota and have relevance for health.”