Dietary fibre, found in fruits, vegetables, and other types of food, is not digested in the small intestine. These, undigested pass through the small intestine, reach the large intestine and colon.
Fibre bulks up food. These facilitate the movement of waste down the large intestine helping in a convenient evacuation.
Fibre-rich food includes wholegrain food products like bread, breakfast cereal, and pasta. Then we have fruits like berries, melons, oranges, and pears. Vegetables like broccoli, carrots, sweet corn, peas, beans, pulses, nuts, and seeds, potatoes with skin, are rich in fibre. In plants, the woody fibre is generally lignin.
Oats and barley contain beta-glucan fibre. Three grams and more of it when consumed daily is said to help reduce cholesterol levels. Dietary fibre helps reduce the risk of cardiovascular disease, type 2 diabetes, and bowel cancer.
The UK government nutrition agency recommends consumption of 30 grams of fibre per day for adults of overages of 17 years. The American Dietetic Association recommends using 25 grams of dietary fibre for adult women and 38 grams for adult men.
The average intake of dietary fibre in the US, these days, is 15 grams per day, much lower than this recommendation. Individuals consuming more than 25 grams per day of dietary fibre were seen to show reduced obesity (Howarth et al., 2001).
Dietitians recommend consuming a fibre-rich diet to individuals suffering from constipation and a low fibre diet when afflicted by diarrhoea. High-fibre diets provide bulk, are more satiating, and have been observed to lower body weights. Consumers, therefore, are turning to fibre supplements and bulk laxatives as additional fibre sources.
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