The Switch Effect on Diabetes: More Than Weight Loss

Why is the switch so much more effective for reversing diabetes than gastric bypass? It’s an uncommon procedure more specifically known as biliopancreatic diversion with duodenal switch. New research in Cell Metabolism provides some answers. Hint: it’s not all about the weight loss.

Better Insulin Sensitivity

Conventional wisdom holds that this procedure is simply a more effective weight loss surgery. It usually produces more weight loss than a gastric bypass, so why shouldn’t it be more effective for reversing diabetes.

But in this new study, senior author Samuel Klein and colleagues controlled carefully for weight loss. They examined the effect of the switch versus bypass on glucose regulation  after 20 percent weight loss. In terms of weight loss, it was an apples-to-apples comparison. However, the metabolic effects were very different. They found “unique metabolic effects on glycemic control.” After a switch, patients absorbed glucose more slowly. Glucose and insulin responses were less. And perhaps most important, insulin sensitivity improved more.

In other words, it’s all about the metabolism, not the weight loss

A Better Option for Some?

The switch accounts for no more than three percent of bariatric surgeries in the U.S. Complication rates are higher. It requires more follow up and closer attention to nutrition. Protein, vitamin, and mineral deficiencies are a bigger risk. Nonetheless, Klein says the switch deserves a closer look for some patients:

Our results help explain the high rate of diabetes remission in patients who have biliopancreatic diversion surgery. These data suggest that we should take a closer look to see whether it might be a better option for some bariatric surgery patients.

This study demonstrates additional metabolic benefits from biliopancreatic diversion, compared to Roux-en-Y gastric bypass. But the type of bariatric surgery performed on any individual patient depends on many considerations, including an assessment of the effectiveness and safety of the procedure, patient preference, and the surgeon’s experience.

Click here for the study and here for more perspective on it from Washington University. For more on the outcomes of the switch versus bypass, click here and here.

Switch, photograph © Jerzy Durczak / flickr

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.


October 6, 2019

One Response to “The Switch Effect on Diabetes: More Than Weight Loss”

  1. October 06, 2019 at 11:55 pm, John Dixon said:

    It’s interesting as the BPD, and BPD-DS have previously been shown to have an early influence on total body insulin sensitivity that is absent with other procedures. This is truly a beyond weight loss effect.