Daily consumption of Bifidobacterium animalis subsp. lactis GCL2505 and inulin for four weeks led to increases in resting energy expenditure of almost 85 kcal per day, according to findings published in Nutrients.
“Clinical trials have demonstrated that GCL2505 is effective in reducing visceral fat, and animal studies have shown that this effect is due to the high production of SCFAs [short chain fatty acids] via the intestinal viability and intestinal proliferation of GCL2505,” wrote scientists from Ezaki Glico Co., Ltd., in Japan. “In addition, GCL2505 in combination with inulin has been shown in clinical trials to reduce body fat, improve vascular endothelial function and improve cognitive function.
“Although a series of research studies have proven the effectiveness of GCL2505 and inulin, the REE improvement effect has been newly revealed in this study. Thus, we can expect that the effects of GCL2505 and inulin on the diseases that constitute metabolic syndrome will contribute to preventing the onset and progression of these diseases in a domino-like fashion, thereby reducing or eliminating the risk of metabolic syndrome.”
Gut health and obesity
The study adds to the ever-growing body of science linking the gut microbiota and obesity, an association first reported in 2006 by Jeffrey Gordon and his group at Washington University in St. Louis. Those early studies revealed 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. This suggested that obesity has a microbial component (Nature, Vol. 444, pp. 1022-1023, 1027-1031).
A 2013 paper in Science (Vol. 341, Issue 6150), also led by Prof. Gordon, found that transplanting gut bacteria from obese humans into germ-free mice leads to greater weight gain and fat accumulation than mice that were given bacteria from the guts of lean humans.
The findings showed that weight and fat gain is influenced by communities of microbes in the gut and their effect on the physical and metabolic traits of the host, leading to metabolic changes in the rodents that are associated with obesity in humans.
This has led many research groups to explore if probiotics and/or prebiotics may help manage weight. A probiotic is defined as a “live microorganisms which when administered in adequate amounts confer a health benefit on the host” – FAO/WHO.
A prebiotic is defined as, “a substrate that is selectively utilized by host microorganisms conferring a health benefit”.
A synbiotic is defined as, “a mixture comprising live microorganisms and substrate(s) selectively utilized by host microorganisms that confers a health benefit on the host”.
Study details
The Japan-based scientists recruited 44 overweight or mildly obese adults to participate in their parallel, placebo-controlled, randomized, double-blind study. The subjects were randomly assigned to receive either the daily synbiotic (10 billion CFUs of GCL2505—commercially named BifiX in Japan—plus 5 g of inulin) or placebo for four weeks. GCL2505and was originally isolated from the feces of healthy adults.
The results showed that the resting energy expenditure score after four weeks of synbiotic supplementation was significantly higher (84.4 kcal/day) compared to the placebo group.
Analysis of feces indicated that the synbiotic led to significant increases in bifidobacteria counts.
“It is speculated that intake of GCL2505 and inulin may increase the concentration of SCFAs in the gut by increasing the total number of bifidobacteria in the gut, thereby stimulating the sympathetic nervous system via GPR41 [G protein-coupled receptor 41] and activating BAT [brown adipose tissue] to improve energy expenditure,” the researchers wrote.
“These results suggest that the intake of GCL2505 and inulin improves the energy balance, which is the underlying cause of obesity,” they concluded. “These results might also suggest the underlying mechanism of the anti-obesity effects of GCL2505 and inulin, and this is the first report of the effects of probiotics and dietary fiber on REE.”
Source: Nutrients
2024, 16(14), 2345; doi: 10.3390/nu16142345
“Effect of Intake of Bifidobacteria and Dietary Fiber on Resting Energy Expenditure: A Randomized, Placebo-Controlled, Double-Blind, Parallel-Group Comparison Study”
Authors: Y. Baba et al.