The Smallest Losers in Bariatric Surgery: Microbes

Forget the Biggest Loser. Perhaps we should be paying more attention to the smallest losers. We mean the microbes in our guts that serve to digest all of that food we eat. New research is making it clear that the gut microbiome changes profoundly after the most effective widely-used weight loss surgery – gastric bypass.

Profound Microbiome Changes in Bypass Versus Band Patients

Zehra Ilhan and colleagues compared the intestinal microbiomes of patients who underwent gastric bypass and gastric banding procedures to matched controls. They found changes in the diversity and character of gut microbes that were distinctive for bypass patients. But perhaps most significantly, they found differences in the metabolic function of those microbes.

In the bypass patients, but not in the banding patients, they found increased amino acid and carbohydrate fermentation products.

This is one of the first studies to show that anatomically different surgeries with different success rates have different microbiome and microbiome-related outcomes. Further, the results indicate that correction of obesity tends to improve related metabolic conditions, including diabetes and high cholesterol.

Co-author John DiBaise explained the importance of this finding:

These new data on microbial community structure and function significantly expand our knowledge on how the microbiome is associated with weight loss following bariatric surgery.

Moving Beyond the Association

The real key will be apply this knowledge to determine the role these microbial changes play. Do microbes cause the metabolic changes for better health? Or are they just coming along for the ride? We’re a long way from having probiotics that would even begin to help with obesity, but it’s a nice aspiration. Or maybe the microbiome will help to better target and personalize obesity treatments for better outcomes.

Regardless, you can be sure we will be hearing a lot from these smallest losers.

Click here for the new study and here for prior research from the same group. For more from MedPage Today, click here. For additional recent research on the microbiome in gastric bypass surgery, click here and here.

Small Details, photograph © fs999 / flickr

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May 31, 2017