Soluble fibers are generally plant-produced carbohydrates that, like cellulose,
are indigestible, but will dissolve in water and therebye form a slippery gel.
Metamucil-the husk of a plant called psyllium-is a good and perhaps familiar
example of soluble dietary fiber. So is fruit pectin, guar gum, xanthan gum and
the fiber in oats that makes oatmeal "gluey" or slimy.
Soluble fibers too are important in human health and weight control and for
largely the same reasons as insoluble fiber.