Benefits of insoluble fibre in the body

What are insoluble fibres used for?

Insoluble fibres do not dissolve in water and have a very high swelling capacity.

The most common are lignin, cellulose and hemicellulose.

They speed up transit and promote satiety, helping to control appetite and weight.

They prevent constipation and promote regular bowel function and good digestive health.

They would increase excretion of carcinogens and prevent certain types of digestive and colon cancers, but they do not have the same benefits as soluble fibre in preventing cardiovascular disease.

What are the sources of insoluble fibre?

Insoluble fibre is found in the skins of vegetables and fruit and in the bran of whole grains.

They do not dissolve in water and their main function is to regulate digestion.

They increase the volume of the gastric bolus, absorbing water along the way and improving intestinal transit.

Most insoluble fibres are resistant to bacterial enzymes, but some forms, such as starches, are fermented in the large intestine.

List of insoluble fibres:

• Whole grain foods
• Wheat bran and maize
• Pulses such as beans and peas
• Nuts and seeds
• Potato peels
• Lignans
• Green beans, cauliflower, courgettes, celery and nopal
• Certain fruits, such as green avocados and bananas
• Peel of certain fruits, including kiwi, grapes and tomatoes