Data from 30 obese women indicated that 16 grams a day of the commercially available Synergy 1 prebiotic from Beneo resulted in significant reductions in levels of the short chain fatty acids acetate and propionate.
“Regarding the possible relationship between levels of SCFA and metabolic parameters associated with obesity, we found in the present study with obese women that the main end products from gut bacterial fermentation like acetate and propionate positively correlated with BMI suggesting that SCFA might be involved in body weight increase,” explained researchers in Clinical Nutrition .
Prebiotics are "non-digestible substances that provide a beneficial physiological effect on the host by selectively stimulating the favorable growth or activity of a limited number of indigenous bacteria".
Gut health and obesity
The study adds to emerging body of science supporting the effects of gut microflora on metabolic factors and obesity.
In 2006, Jeffrey Gordon and his group at Washington University in St. Louis reported in Nature (Vol. 444, pp. 1022-1023 , 1027-1031 ) that microbial populations in the gut are different between obese and lean people, and that when the obese people lost weight their microflora reverted back to that observed in a lean person, suggesting that obesity may have a microbial component.
Dr Gordon and his group recently pushed back the scientific boundaries even further in this area. In an ‘elegant’ study, the St Louis-based scientists reported that probiotics in a yogurt did not colonize the gut microflora when studied in identical twins, but additional study in mice revealed that ingestion of probiotic bacteria produced a change in many metabolic pathways, particularly those related to carbohydrate metabolism (Science Translational Medicine , Vol. 3, 106ra106).
The new study examined how prebiotic supplement could affect gut microbial populations and short chain fatty acids in obese women.
Thirty obese women were recruited to participate in the randomized, double blind, parallel, placebo-controlled trial, and randomly assigned to receive either the prebiotic Synergy 1 (16 g/day) or placebo (maltodextrin) for three months.
Results showed that the prebiotic group displayed significant increase in levels of Bifidobacterium longum, B. pseudocatenulatum and B. adolescentis.
Short chain fatty acid (SCFA) levels were also reduced in the prebiotic group, and were correlated with BMI, and a reduction in insulin levels and the homeostasis model assessment (HOMA).
“Insulin levels and HOMA index are considered as markers of metabolic syndrome and it has been previously reported that SCFA are additional sources of energy for the body and are involved in glucose and lipid metabolism in the host,” explained the researchers. “Interestingly, the prebiotic treatment with [prebiotic fibers] in our study allows decreasing SCFA level in the feces of obese women inverting the obese profile characterized by the high production of these metabolites, were significantly lower in prebiotic than in placebo group after the treatment.”
The researchers concluded: “The prebiotic [Inulin-type fructans] intervention in obese women selectively modulates certain Bifidobacterium species that are inversely correlated with deleterious biological parameters for the host. This prebiotic treatment could also invert the higher fecal SCFA concentration observed in obese individuals and the potential mechanism of energy sparing in these individuals that could be associated with metabolic risk factors.”
Source: Clinical Nutrition
Published online ahead of print, doi: 10.1016/j.clnu.2014.06.001
“Inulin-type fructans modulate intestinal Bifidobacterium species populations and decrease fecal short-chain fatty acids in obese women”
Source: N. Salazar, E.M. Dewulf, A.M. Neyrinck, L.B. Bindels, P.D. Cani, et al