Principal sources and dietary importance of Dietary fibre (Roughage)

Question 1

Fibre (Principal sources)

Answer 1

Rich sources of fibre are fresh fruits and vegetables, bran, wholemeal bread and unpolished rice

Question 2

Fibre (Dietary importance)

Answer 2

Fibre prevents constipation
- The fibre itself and bacteria which multiply from feeding on it, add bulk to the contents of the colon and help it to retain water. This softens the faeces and reduces the time needed for the undigested residues to pass out of the body, preventing constipation
Fibre stimulates peristalsis
- Food moves through the canal because of peristalsis. The muscles are stimulated to do this when there is food in the alimentary canal. Soft foods do not stimulate muscles very much. Instead, they are stimulated by harder, less digestible food like fibre. Thus, fibre keeps the digestive system in good working order.