Does glucomannan work?

Overall Effectiveness Rating for Glucomannan

The overall effectiveness rating for glucomannan is 1.8 out of 3. This rating means there is some evidence that using glucomannan may lead to positive results. This rating also means that some evidence does not back up all claims. Below you can find individual ratings for specific claims.

Overall Confidence Rating for Glucomannan

There are 4 studies in the database on glucomannan; the confidence rating is 40. A score above 80 means the effectiveness rating for this supplement is reliable. A score under 80 means there is insufficient evidence to ensure a reliable effectiveness rating. Note, this rating is for glucomannan as a whole. There are also individual ratings for the claims below.

Products Containing Glucomannan

Products Containing Glucomannan
Nano Shred Deluxe
Nano Shred Max
Instant Knock Out
Full list of all 3 products containing Glucomannan.

Individual Claims

The overall ratings above do no necessarily reflect each claim about glucomannan. Individual claims can have higher or lower ratings. For example, some supplements may have a lot of backing for one claim, but be completely useless for another. Click on claims below for more information.

Body Composition (weight, muscle, body fat) Claims Effectiveness Rating Confidence Rating
decrease body fat
increase weight loss

Energy Balance (calories in & calories out) Claims Effectiveness Rating Confidence Rating
increase satiety
decrease calorie intake

Cardiovascular Health Claims Effectiveness Rating Confidence Rating
lower blood pressure
lower LDL (bad) cholesterol levels
increase HDL (good) cholesterol levels
lower total cholesterol levels
lower triglyceride levels

General Health Claims Effectiveness Rating Confidence Rating
lower fasting glucose


Title of Study
A Glucomannan and Chitosan Fiber Supplement Decreases Plasma Cholesterol and Increases Cholesterol Excretion in Overweight Normocholesterolemic Humans
Effect of short-term ingestion of konjac glucomannan on serum cholesterol in healthy men
Konjac Supplement Alleviated Hypercholesterolemia and Hyperglycemia in Type 2 Diabetic Subjects—A Randomized Double-Blind Trial
Safety and Efficacy of Glucomannan for Weight Loss in Overweight and Moderately Obese Adults