Fibre
The fibre can be divided into two categories, and both of them are needed to be healthy :
1) Soluble fibre which leads to steadier energy;
When you eat plenty of foods which is reach in soluble fibre (oats, pulses, nuts, seeds, fruits, vegetables) it helps to reduce blood cholesterol, to steady energy level and stabilize the mood. It gives a gentle rise in blood sugar which lasts longer. It is especially a great advantage for overweight and diabetic person to eat as much food that consists of soluble fibre as possible.
2) Insoluble fibre which speeds the passage of waste;
When you eat plenty of foods which is reach in insoluble fibre (cereals, grains and especially unrefined wholegrains, unpeeled fruits and vegetables) it helps food waste to pass through the digestive track quickly and more easily and also prevents constipation.