Description:

Dietary fiber is found in the indigestible parts of plants. Good sources of fiber include wholegrain foods, fruits and vegetables. Drinking lots of fluid is also important to avoid constipation.The main role of fiber is to keep the digestive system healthy. Fiber has also been shown to benefit diabetes, blood cholesterol levels and weight control.

 Lowering blood cholesterol

Recently, there has been a great deal of interest in oat bran, since some studies showed that regular intake of foods high in soluble fiber - such as oat bran, baked beans and soybeans - reduced blood cholesterol levels. When blood cholesterol levels are high, fatty streaks and plaques are deposited along the walls of arteries. This can make them dangerously narrow and lead to an increased risk of coronary heart disease.

It is thought that soluble fibre lowers blood cholesterol by binding bile acids (which are made from cholesterol to digest dietary fats) and then excreting them. Cereal fiber seems to be more protective against coronary heart disease than the fiber from fruit and vegetables.

A method of weight control

In many cases, people who are overweight or obese have been shown to lose significant amounts of excess body fat simply by increasing the amount of dietary fibre, especially soluble fiber, in their daily diet.

Fibrous foods are often bulky and, therefore, filling. They also tend to be low in fat. Soluble fiber forms a gel that slows down the emptying of the stomach and the transit time of food through the digestive system. This extends the time a person feels satisfied or ‘full’. It also delays the absorption of sugars from the intestines. This helps to maintain lower blood sugar levels and prevent a rapid rise in blood insulin levels, which has been linked with obesity and an increased risk of diabetes.

The extra chewing time often required of high fibre foods also helps contribute to feeling satisfied. As a result, a person on a high fibre diet is likely to eat less food and so consume less kilojoules (calories).

Good for people with diabetes

For people with diabetes, eating a diet high in fibre slows glucose absorption from the small intestine into the blood. This reduces the possibility of a surge of insulin, the hormone produced by the pancreas to stabilise blood glucose levels.