When weight loss surgery works, it's only because of bacteria changes in the gut

Monday, June 24, 2013 by: Lance Johnson
Tags: gastric bypass, gut flora, weight loss

(NaturalNews) Each year, roughly 200,000 morbidly obese Americans go under the knife for weight loss surgery. Most all doctors perform this surgery to save lives and it seems to be working for many. According to the American Society of Metabolic and Bariatric Surgery, after weight loss surgery, patients lose up to 60 percent of their former weight and up to 77 percent just a year later. They state that these surgeries are "preventing and improving diseases which include heart disease, cancers, and Type II diabetes."

On the surface these surgeries appear to work, but a new study points out that there's more to the story, that the weight loss surgery itself isn't the reason why patients are losing weight and keeping it off. A new study links the success of weight loss after surgery to significant bacteria changes in the gut.

Gastric bypass surgeries succeed because of changes in gut bacteria

The most common bariatric surgery, the Roux-en-Y gastric bypass, makes the stomach smaller by rearranging the digestive tract to prevent excess absorption of calories. Sounds simple and effective, but there may be more to it. Researchers from the Massachusetts General Hospital and Harvard University found out that, during the operation, significant changes in gut bacteria occur. In successful weight loss surgeries, beneficial "slimming" bacteria override the bad, bringing about a new friendly gut flora that encourages better utilization of calories and nutrients.

Changes in gut bacteria may be the weight loss secret

In a detailed experiment with mice, the researchers wanted to find out why gastric bypass surgeries were effective. They wanted to find out if these surgeries were even necessary for weight loss, or if gut bacteria is the answer. Here's what they found:

After performing the Roux-en-Y gastric bypass surgery on one group of mice, the rodents lost and kept off 29 percent of their previous weight. The researchers then transferred this new gut flora to another group of obese mice that hadn't undergone surgery. This group of mice lost weight and fat without the surgery, leading the researchers to believe that gut bacteria is a secret weight loss tool.

Furthermore, the scientists performed "sham" gastric bypass surgeries on another group of mice. They made incisions in the mice, but ultimately stapled their intestinal tract back to its normal state. These mice lost no weight and had no changes in gut bacteria. The researchers transferred their gut flora to another group of obese mice. These mice lost no weight either. This further explained that significant changes in gut bacteria are the reason why weight loss surgeries are successful.

Author of the study, Dr. Lee Kaplan, said, "The effects of gastric bypass are not just anatomical, as we thought. They're also physiological. Now we need to learn more about how the microbiota exert their effects."

Skipping gastric bypass and opting for changes in gut bacteria instead

By narrowing in on gut bacteria composition, further studies showed that the "slimming" bacteria helped raise the body's metabolism, helping patients burn calories faster. The "slimming" bacteria were also found to extract fewer calories from food, whereas fattening bacteria extract as much as possible.

By changing a patient's diet to encourage better "slimming" gut flora, doctors can help patients skip past the pricey and risky gastric bypass surgery to encourage weight loss the physiological way, not the anatomical way. By transferring "slimming" bacteria into obese people, doctors could assist the weight loss process without performing extensive surgery.

Breathing tests can indicate the presence of fattening gut flora

A recent study published in the Journal of Clinical Endocrinology & Metabolism, reports that breath tests can help indicate who is harboring fattening gut bacteria and who isn't. Breath that tests for high concentrations of both hydrogen and methane gas is most likely breath of someone who has a higher body mass index. This hydrogen and methane breath is associated with the bacterial strain Methanobrevibacter smithii, which is a fattening bacterium that extracts as many calories from food as possible.

By testing breath and gut bacteria, doctors can help obese patients change their lifestyle to build better "slimming" gut flora. This will promote a better metabolism and help create a natural weight loss environment. The gastric bypass surgery welcomes "slimming" gut bacteria, but this risky procedure can be bypassed altogether, as doctors and patients learn how to modify gut bacteria instead of gut anatomy.

Sources for this article include:

http://www.reuters.com

http://health.usnews.com

http://www.nytimes.com