Science brief
Weight loss leads to significant gut microbiota changes
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).
A new study in the American Journal of Clinical Nutrition indicates that gastric bypass surgery, one of the most efficient procedures for treating morbid obesity, resulted in increased richness of gut microbiota, with 37% of increased bacteria belonging to Proteobacteria.
The surgery also led to changes in 14 discriminant bacterial genera and 202 genes in white adipose tissue (fat tissue).
These results show an increase in gut microbiota richness and in the number of associations between gut microbiota and white adipose tissue genes after [gastric bypass surgery] in obesity,” wrote researchers from the Institute of Cardiometabolism and Nutrition, Heart and Metabolism in Paris, France.
“These findings stimulate deeper explorations of the mechanisms linking gut microbiome and white adipose tissue pathological alterations in human obesity and its changes after weight loss.”
Source: American Journal of Clinical Nutrition
Published online ahead of print, doi: 10.3945/ajcn.113.058743
“Gut microbiota after gastric bypass in human obesity: increased richness and associations of bacterial genera with adipose tissue genes”
Authors: L-C. Kong, J. Tap, J. Aron-Wisnewsky, et al
