Success Of Bariatric Surgery Is Linked To Gut Germs, New Study

Success Of Bariatric Surgery Is Linked To Gut Germs, New Study

How many pounds someone loses after weight-loss surgery is linked to the types of germs they have in their gut, new research suggests.The study found that higher levels of certain microbes — specifically those that produce methane — may translate to slightly less weight loss. These germs are known as methanogens.”Our new study suggests that gastrointestinal colonization with methanogens makes it harder to lose weight after bariatric surgery,” lead investigator Dr. Ruchi Mathur said in an Endocrine Society news release.The researchers reached their conclusions by studying the breath of more than 150 patients — 112 women and 44 men — who’d undergone weight loss surgery, also known as bariatric surgery, four to 12 months earlier. A person’s breath offers insight into the germs in his or her digestive system.

Thirteen of the patients tested positive for methane and hydrogen. On average, the decrease in their body-mass index — a measure of obesity — was slightly more than 20 percent compared to 23.5 percent for the other patients.Mathur, director of the Diabetes Outpatient Treatment and Education Center at Cedars-Sinai, Los Angeles, said too many methane-producing germs could alter a person’s metabolism. But it may be possible to change a person’s gut germs through medication or diet.”We believe such interventions will help these patients achieve their weight loss goals after bariatric surgery,” Mathur said.The study was to be presented Thursday at the annual meeting of the Endocrine Society in San Diego. Studies released at meetings should be considered preliminary until they are published in a peer-reviewed medical journal.

A new study, led by researchers at Arizona State University, reveals that Bariatric Surgery profoundly changes which microbes can survive and thrive in the human gut, in turn leading to weight normalisation.
This change in the way in which constituent parts of the microbiome are interrelated or arranged impacts on the outcome of the procedure typically undergone by overweightpeople with type 2 diabetes or those who are obese. So far, it has been unclear to what extent those changes in the human microbiome matter, but we know from previous research that many diseases are linked to such changes in what’s called dysbiosis.This study is one of the first to suggest that that these alterations can be beneficial too, with findings that echo a paperreleased last year by Israeli researchers on the “yoyo-effect” while dieting.
The idea behind the yoyo-effect is that if you lose weight, you suddenly become more prone to putting it back on. At the time of this past study, it emerged that there are evident microbiome changes involved in this yoyo-effect.

Similarly, the current study shows that with Bariatric Surgery, the gut microbes are not just going along for the ride but they are also grabbing the wheel. A shift in gut flora occurs when undergoing a gastric bypass as the sugery involves cuts in prime microbial residential sites, notably around the small intestine where bacterial flora serves a wide range of intestinal functions.The researchers from Arizona found that patients who underwent the procedure experienced a total and permanent re-mapping of their microbiomes, with species that ameliorate the yo-yo effect and promote weight loss.

Interestingly, the bypass didn’t merely shift their microbial profile. It actually created an entirely new, healthier ecosystem of microbes, showing that the repopulation of gut microbes is a dynamic, ever-evolving process. These changes seem to happen spontaneously as the dramatic organ-reorganisation that is gastric bypass changes the environment in the gut to one less acidic with more oxygen. This allows microbes, formerly unable to survive in the gut, to flourish.As it turns out, many of the new residents produce molecules that signal appetite-suppressing hormones and other neurological pathways that control eating, which could explain part of the weight loss effect post-surgery. Physiological problems can arise when the balance of microbes in the gut is compromised, but these findings show that Bariatric Surgery appears to benefit the gut microbiota leading to improved weight loss.source