OSH vs Vegetables and Fiber

Hydrogels, Balloons, and Fiber in Obesity Care

This is a time of great change in obesity care. Right now, semaglutide is on its way to becoming a blockbuster new drug. That’s because it can help people with obesity control their condition better – with more weight loss – than older anti-obesity medicines. But at the same time, new non-drug, non-systemic options with modest effectiveness are making their way into the market for obesity care based on the technology of superabsorbent hydrogels. Some of these look like a pill, but they have more in common with a gastric balloon than a medicine.

A new paper by Louis Aronne and colleagues in Obesity Science and Practice offers the scientific background on this distinctive technology. This is the technology behind the product called Plenity.

Going Beyond Fiber

The interest in a role for dietary fiber in managing obesity dates back to the 1970s and before. It has continues stronger than ever with attention to the interaction between fiber, the microbiome, and obesity.

But superabsorbent hydrogels are not the same as dietary fiber. Whereas dietary fibers form a viscous liquid in the gut, a superabsorbent hydrogel is different. When it absorbs water, it forms a semi-solid gel. In the form of Plenity, it forms a mass that’s more like vegetables you’ve eaten than a glass of Metamucil you might drink as a fiber supplement.

Thus, in the form of Plenity, a superabsorbent hydrogel can be a safe, nonsystemic tool for modest weight loss. In the 24-week GLOW study, people with overweight and mild obesity lost 6.4% of their starting weight.

In contrast, evidence that fiber supplements produce clinically meaningful weight loss is lacking.

Future Possibilities

Aronne et al describe ongoing work to make use of superabsorbent hydrogels obesity care:

“Three approaches in development utilize superabsorbent hydrogel technologies to support an intragastric balloon‐like structure, solely occupying space in the stomach and displacing the meal: (1) a pufferfish-inspired device; (2) Epitomee, a pH‐sensitive self‐expanding hydrogel device; and (3) a light‐degradable hydrogel used to control balloon deflation. These new approaches that utilize superabsorbent hydrogel technology offer a wide range of clinical applicability and have the potential to broaden the weight management treatment landscape.”

This is fascinating stuff. In obesity care, one size does not fit all. Surgery is very effective, but many people shy away from it. Anti-obesity meds are becoming more and more effective, but some people simply don’t like taking drugs. So having non-drug, non-surgical options that can be effective and safe is a good thing.

Click here for the paper by Aronne et al and here for the pivotal study of Plenity for weight loss.

Viscoelastic properties of superabsorbent hydrogel, figure 1 from Arrone et al, 2021, in Obesity Science and Practice, licensed under CC BY 4.0.

Editor’s note: ConscienHealth’s founder, Ted Kyle, has provided consulting services to Gelesis, Inc, the makers of Plenity, though Gelesis had no role in the content of this post. 

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December 8, 2021