After an exhausted search on Fiber, I have come across what seems to be the best form of fiber one can ingest on a supplemental basis.(next to psyllium, which I will come to in a second) You see, Konjac (glucommanan) is a vital source of soluble fiber. Soluble fiber is the type of fiber that binds and blocks bile acids (fat transporters that suck up fat and increase your waist size) preventing them from getting all the fat particles out of your food. Soluble fiber also traps carbs in its gelatinous state, and fills your tummy in its gelatinous state (makes you feel full). This leaves proteins unaffected which happen to be that which least contribute to your waist size.
In sum, soluble fiber like konjac can reduce your waist size, reduce your cholesterol, reduce your chances for diabetes all in one swift gulp. Start slow but get your fiber supplement up to 4gm with each meal if you are a big eater (likely so in America). Of note 20-35gm a day are recommended of TOTAL FIBER. You can get the rest of your fiber (specifically insoluble fiber) through the normal eating of various fiberous foods.
If glucomannan or Konjac gives you gas, you may want to consider Psyllium husk supplement. This is a type of fiber that contains both soluble and insoluble fiber which may provide you with a balanced approach to fiber supplementation. This means it will give you the same benefits of soluble fiber and provide you with relief of constipation and easier passage of stool. If you are taking Psyllium fiber, the recommended amount is 3-4gm three times a day. Start with much smaller amounts and work your way up, your intestines will need to get used to the change in your fiber load.