Fibre exists tin abundance in all plant-based foods. It is that part of the plant which cannot be digested. Therefore it passes through the GI tract unchanged. It does not provide energy or nutrients, and yet it is of utmost importance to keep us in good health. For one, it acts like a broom and cleans the body of toxins, fats and wastes. Think of fibre as a sponge passing through your gastrointestinal tract. It has water holding and bulk forming properties.