Our intestines are populated by a vast number of bacteria. Thousands of microbial species help us in digesting our food, but can also cause various health problems when the bacterial balance is not right. How about treating obesity with modified gut flora?
An interesting observation was published this week in the Science magazine. Rats with sterile bacteria-free guts were transplanted with the bacterial cultures taken from the intestines of two identical twins, one of which was lean, and another obese. The rats then were kept in the identical conditions and on the identical diet for a certain period of time. It turned out that rats that received bacteria from obese twins gained some extra weight, while the rats that received bacteria from lean twins maintained a normal body mass.
The bacterial composition of intestinal microflora is different in obese and lean people. The bacterial species more common in lean individuals are capable of cleaving the fibers into short chain fatty acids and thus indirectly prevent the accumulation of body fat.
Bacterial supplementation can be a modifying factor in obesity
It is unlikely that the approach demonstrated on rats will ever be used directly on humans. Transplantation of intestinal bacterial cultures is associated with a higher risk of infectious diseases. It is more likely that further research will aim to identify those species of bacterial that are associated with the benefits for weight management. Once identified, these species can be supplemented for people with an obesity problem.
Manipulations of the bacterial composition in the gut might be a helpful tool in treating other problems such as inflammatory bowel disease and Crohn’s disease. Some difficult C. difficile infections can already be treated by bacterial transplantations from healthy people.
The authors of the study point out that bacterial microflora modification would not help if the general diet remains unhealthy. Changing the bacterial balance in the intestines is only one of the factors influencing the body weight.
The composition of bacterial species in the gut influences the digestion efficiency and body weight. Manipulations of microflora such as bacterial transplantation or supplementation may help in treating obesity.
- Vanessa K. Ridaura, Jeremiah J. Faith, Federico E. Rey et al. (6 September 2013) Gut Microbiota from Twins Discordant for Obesity Modulate Metabolism in Mice. Science: Vol. 341 no. 6150. DOI:10.1126/science.1241214