Fiber cannot be digested by humans. It has no calories because the body cannot absorb it. Soluble fiber attracts water and turns to gel during digestion. This slows digestion and the rate of nutrient absorption from the stomach and intestine. It is found in oat bran, barley, nuts, seeds, beans, lentils, peas, and some fruits and vegetables.
Insoluble fiber is found in foods such as wheat bran, vegetables and whole grains.
It appears to speed the passage of foods through the stomach and intestines and adds bulk to the stool. Dietary fiber provides a feeling of fullness and adds bulk in the diet. This assists digestion and elimination. Including fiber in your daily diet helps prevent many problems and brings many benefits. It may be helpful in controlling weight by making you feel full sooner.