Can friendly bacteria help weight loss?
Obesity is a growing global concern that costs national health services billions each year. Evidence has already shown that probiotic bacteria have many beneficial physiological effects, including nutrient assimilation and energy regulation, which has prompted scientists to begin research into a possible link between our microbiota and weight loss.
There have been a number of studies exploring the possibility of using probiotics and/or prebiotics to control obesity and weight management. Although current evidence is inconclusive in terms of suggesting a specific probiotic strain or type of prebiotic, this early research looks promising, and definitely encourages further studies to find out more!
Encouraging early probiotic studies
Healthcare professionals might be interested to learn that several scientific studies have investigated the link between probiotics and weight loss.
A small 2008 study1 actually found that rats given acidophilus showed weight loss compared to rats not given probiotics. Those given acidophilus showed increased levels of leptin, a protein found to decrease the appetite and increase the metabolism.
A further study in December 2012 2 by the Irish Agriculture and Food Development Authority with Cork University found that altering Lactobacillus probiotics in a certain way could lead to the production of molecules which reduce levels of fat tissue in the body. Levels of t10, c12 CLA (a molecule shown to shrink fat cells) in the body fat of mice fed this special Lactobacillus strain were four times greater than in the mice not fed this strain.
More recently, in 2015 a small study3 in mice found that the bacteria species Clostridium ramosum showed a strong association to weight gain and an increased risk of obesity. Lead researcher, Michael Blaut, and his team observed the effects of a C. ramosum on 3 groups of mice. Group 1 had a simplified human intestinal microbiota composition, including C. ramosum. Group 2 had the same microbiota, except it didn't include C. ramosum, and group 3 had a gut microbiota consisting solely of C. ramosum. All three groups were fed a high fat diet. The researchers noted that both groups that contained C ramosum bacteria gained significantly more weight that the group without.
Another mouse study in 20154, found that the E. coli Nissle 1917 also exhibited a potential benefit in weight management. Scientists observed that mice given E. coli Nissle 1917 had reduced appetites, lowered body fat and a lowered risk of developing diabetes, even when fed a high-fat diet.
What about prebiotics?
Other studies show that prebiotics such as FOS can increase levels of the satiety hormone, glucagon-like peptide (GLP-1), helping to reduce food intake and improving the blood lipid profile. For further information on prebiotics and weight loss, see the following article by Georges Mouton, internationally acclaimed Doctor of functional medicine: - The Uses of Prebiotics.
A meta-analysis recently published has concluded there is a lack of robust evidence that prebiotics or synbiotics aid weight loss5. Rather than a disappointing result, this is something that researchers in this field are already acutely aware of. It would seem that this meta-analysis study has been conducted prematurely, when we know the clinical trial research still has a long way to go. We shouldn't be disheartened by this publication but rather see it as a reminder of where we are in the research process. Watch this space!
Probiotics for bloating
Lactococcus lactis Rosell-1058 - this probiotic strain has been found to produce two specific enzymes (a-glucosidase and b-galactosidase) that help to digest troublesome foods such as starch and lactose, which can trigger bloating in those with a food intolerance6.
Bifidobacterium bifidum Rosell-71 - Bifidobacteria have been found to compete with methane producing bacteria which often causes bloating7. The B. bifidum Rosell-71 strain also helps promote healthy bowel movements, so food doesn't stagnate and ferment in the gut6.
Lactobacillus acidophilus Rosell-52 - this specific strain has been shown to reduce the negative effects of stress on the body, which often triggers bloating8.
Lactobacillus casei Rosell-215 - produces lactic acid, which decreases pH in the gut so bad bacteria & yeasts which cause bloating cannot overgrow6.
1. Sousa, R. et al. (2008) Effect of Lactobacillus acidophilus on supernatants on body weight and leptin expression in rats. BMC Complementary and Alternative Medicine. 8:5.
2. Clarke, S. et al. (2012) The gut microbiota and its relationship to diet and obesity. Gut microbes, 3:3, 186-202.
3. Blaut, M. et al. (2015) Dynamics of infant gut microbiota are influenced by delivery mode and gestational duration and are associated with subsequent adoposity. mBio. Published online ahead of print.
4. Findings presented at a meeting of the American Chemical Society, "Incorporations of therapeutic bacteria into the gut microbiome for treatment of obesity.
5 Fernandez (2017) Effects of inulin-type fructans, galacto-oligosaccharides and related synbiotics on inflammatory markers in adult patients with overweight or obesity: A systematic review.
6. The effects of a fermented milk product containing Bifidobacterium lactis DN-173 010 on abdominal distension and gastrointestinal transit in irritable bowel syndrome with constipation. A.Agrawal, L.A. Houghton, J.Morris, S.Jakob, First published 17 September 2008
7. Institut Rosell, 2012, in vitro studies
8. Picard, et al. (2005) Review article: Bifidobacteria as proiotic agents - physiological effects and clinical benefits. Aliment. Pharmacol. Ther. 22(6): 495-512.9. Messaoudi, et al. (2011) Assessment of psychotropic-like properties of a probiotic formulation (Lactobacillus helveticus R0052 and Bifidobacterium longum R0175) in rats and human subjects. The British Journal of Nutrition, 105(05):755-765.