Soluble fibre has been linked to a number of health benefits. It is distinct from insoluble by the simple fact that soluble fibre happens to be soluble in water. However, because of this fact, soluble fibre has some profoundly different qualities from insoluble fibre.
Soluble fibre is useful for the following reasons:
Like insoluble fibre, soluble fibre helps with digestion. However, insoluble fibre plays a different role in digestion. Rather than being simple "roughage", it actually helps to bind the contents of the intestine, forming a gel that helps the contents to flow better. Soluble fibre is thus useful for those with any bowel irregularity, whether too-infrequent or too-frequent.
It is now firmly believed that soluble fibre helps to reduce cholesterol. This is believed to be because of its binding ability: the cholesterol passes through the gut rather than being absorbed.
Soluble Fibre Supplements
These supplements are not "food" as such, but preparations that can be added to food in order to boost its soluble fibre content.