Konjac Glucomannan is the single most-studied ingredient in RetraBurn, and it's worth understanding exactly what the research does and doesn't say.
Glucomannan is a soluble fiber extracted from the root of the konjac plant. When it absorbs water, it expands significantly — which is the whole mechanism behind its association with fullness.
Studies indexed on PubMed have looked at glucomannan's association with satiety and appetite. The general finding is that fiber which expands in the stomach can contribute to a feeling of fullness, which may support eating less at a given meal.
This is the part that's easy to skip past: glucomannan needs water to do anything. Taking it without a full glass of water isn't just less effective, it's a genuine safety issue — the fiber can expand in the throat rather than the stomach if it doesn't have enough liquid to work with.
Glucomannan isn't a stimulant, an appetite-suppressant drug, or a guaranteed fix. It's a fiber that may help you feel fuller as part of a normal meal — nothing more dramatic than that.
If you're looking for a fiber-based approach to portion control rather than a stimulant, this is exactly the mechanism RetraBurn is built around. See our full ingredients page for how it fits with the other three core ingredients.