Fibre is a type of carbohydrate that cannot be digested in the stomach or small intestine but passes through to the large intestine. As fibre moves through the large intestine, bacteria break down much of the fibre. As they digest the fibre, these bacteria multiply and produce butyric acid, which has been shown to give protection against bowel cancer. Therefore consuming fibre is important for intestinal health. Fibre is found in all plants eaten for food, such as fruit, vegetables, grains and legumes.
Fibre is commonly categorised depending on how easily it dissolves in water. Soluble fibre partially dissolves in water and is found in oat bran, nuts, seeds, beans, apples and pears. This fibre has been shown to decrease the glycaemic index of carbohydrate foods by slowing the release of glucose from food. Insoluble fibre does not dissolve in water and is found in wholegrains, brown rice and a range of vegetables, including carrots and courgettes. Insoluble fibre is responsible for preventing and treating constipation.
Fibre appears to reduce the risk of various conditions, such as heart disease and type 2 diabetes.
Recommended daily intakes for fibre
It is recommended that New Zealanders should consume 25-30 grams of fibre per day. To achieve that amount of fibre it important to consume 5-6 servings of breads/cereals per day as well as at least three servings of vegetables per day. Some suggestions on how to increase fibre intake follow:
- Eat some wholegrain breads and brown rice as well as white bread and white rice.
- Eat whole fruits rather than fruit juices.
- Choose wholegrain cereals at breakfast time.
- Try raw vegetables for snacks rather than fatty or high-sugar snacks.
- Keep the skins on fruit and vegetables.