Fibre is the indigestible part of carbohydrates - this is the structural part of plant-derived foods. The highest concentrations are in the plants in their natural state, in an unprocessed form.
To get the most fibre, try eating the skin of fruits and vegetables, as well as reducing cooking time. Additionally, go for wholegrain breads, cereals, rice, pasta and legumes.
Think of fibre as a tool for exercising the intestinal tract muscles, which are required to move food wastes through our gut. If we have a consistently low-fibre intake, these muscles become slack and cannot move food through our gut as they should. Additionally, we will then have less bulk in our food, so this compounds the problem and results in constipation.
Along with relieving constipation and maintaining GI (gastro intestinal) health, a diet high in fibre may also have the following health benefits:
- Weight control - while the bulky nature of fibrous foods can leave us feeling fuller, they are also slower to be released into the small intestine - which results in a slower release of glucose into the blood. Additionally high fibre foods tend to be lower in calories than foods containing less fibre, because they are lower in fat and sugars.
- Some fibres can interfere with the absorption of fat and cholesterol eaten in the same meal - this has the potential to help reduce blood cholesterol concentrations and may protect against heart disease.
- High fibre foods tend to contain high levels of vitamins and antioxidants, which have been linked to lower levels of all types of cancers.
- Incidence of colon cancer is believed to be reduced in those eating a high fibre diet.
- Low incidences of type 2 diabetes have been seen in populations who eat high levels of fibre. Additionally soluble fibre slows the absorption of glucose, which then reduces the peaks and troughs in blood glucose levels, which can make diabetes management difficult.
- Strong GI tract muscles develop and reduce the likelihood of developing diverticulitis.
- There are a number of different types of dietary fibre. The three major types are soluble fibre, insoluble fibre and resistant starch. (Although it is not actually a fibre, resistant starch is now being recognised as a member of the 'fibre family' due to its similar effects on the body.)
This component dissolves in water to form a gel. This slows down glucose absorption, so helps to control blood sugar in people with diabetes and is beneficial to help lower blood cholesterol levels. Soluble fibre is found in fruits, vegetables, dried peas, soybeans, lentils, oats, rice and barley.
This component does not dissolve in water and as a result its 'bulking properties' helps keep us 'regular'. Foods containing insoluble fibre include wholegrain and wholemeal wheat-based breads, cereals and pasta.
This is a type of starch found in plant foods that escapes digestion in the small intestine. Resistant starch may provide similar benefits to other types of fibre -such as helping to prevent constipation. Foods containing resistant starch include; firm bananas, roasted chickpeas, boiled long-grain white rice, baked beans, cooked and cooled potato, as well as cornflakes.