Obesity and Gut Bacteria

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It has often been said that “microbes rule the world,” and now researchers are finding that the microbes that call the human gut their home may even play a role in weight maintenance. Unlocking the secrets to this role played by gut bacteria may point the way toward helping those who struggle with overweight and obesity.

What Are Gut Bacteria?

The human gut is home to millions of microorganisms, collectively referred to as “gut flora” or “gut microbiota,” that coexist with us, helping us to digest our food, and perhaps even playing a role in keeping down inflammation, preventing heart disease, and maintaining gastrointestinal health.

Thus, researchers are discovering that the composition of a person’s gut flora—the different kinds of gut bacteria and their relative concentrations in each person’s gut—may play a role in that person’s susceptibility to chronic diseases like obesity, diabetes, and heart disease. The many roles that may be played by gut bacteria constitute an area of active ongoing research.

Gut Bacteria and Inflammation

Recent studies have found that certain gut bacteria can contribute to the onset of low-level, chronic (constant) inflammation that is associated with metabolic disorders such as insulin resistance, type 2 diabetes, obesity, and fatty liver disease.

Recent findings reveal that there are complex interactions between gut bacteria and numerous body organ systems, such as the liver, brain, muscles, and adipose (fat) tissue. Through these interactions, the gut microbiota can play a tremendous and complicated role in bodily functions.

These findings have led to further research investigations into not only the roles that gut bacteria play in our bodies, but how these discoveries may be used to create treatments for many of these same chronic diseases.

Gut Bacteria That Can Suppress Appetite

An exciting new line of research is looking at engineering gut bacteria to suppress appetite and protect against the development of obesity.

The laboratory of Sean S. Davies, PhD, Assistant Professor of Pharmacology at Vanderbilt University School of Medicine, is doing just this.

In a recent study, Dr. Davies and colleagues found that specially-engineered bacteria introduced into the gut microbiota of mice reduced the levels of obesity in these mice when they were fed a high-fat diet. While this still has a long way to go to reach a similar level of research in humans, it is an important first step in identifying a possible new pathway for the treatment and prevention of obesity.

Sources

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Chen Z, Guo L, Zhang Y, L Walzem R, et al. Incorporation of therapeutically modified bacteria into gut microbiota inhibits obesity. J Clin Invest 2014;124:3391-406.

Geurts L, Nevrinck AM, Delzenne NM, Knauf C, Cani PD. Gut microbiota controls adipose tissue expansion, gut barrier and glucose metabolism: novel insights into molecular targets and interventions using prebiotics. Benef Microbes 2014;5:3-17.

Everard A, Cani PD. Diabetes, obesity and gut microbiota. Best Pract Res Clin Gastroenterol 2013;27:73-83.

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