Although, Phenocal makes use of several powerful weight loss ingredients, the exact quantities of those ingredients is NOT known, and chances are they are low enough to NOT provide the dramatic results that the product is offering. But, Phenocal is one of the few products in the market that combines glucomannan with thermogenic ingredients like green tea, and cayenne pepper. That raises the chances of this product being a success. However, we'd recommend another similar product Instant Knockout that has the same combination of ingredients - fat blocker like glucomannan, and thermogenic ingredients. Instant Knockout is from a more reputed company, lists out its ingredients in precise details, endorsed by several people from the fitness community and has lots of favorable user reviews. So, it beats Phenocal, in the area of credibility.