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How do soluble and insoluble fibre differ?

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A woman with curly hair and a handbag shops at a busy outdoor farmer's market in Bulgaria, surrounded by stalls filled with fresh fruits and vegetables. — nutrition Vegetables are an important part of a balanced diet.

Dietary fibre consists of plant-based compounds that the human intestine cannot digest. While both types provide health benefits, they differ in their physical properties and physiological effects.1

Insoluble Fibre

Insoluble fibre does not dissolve in water. Its primary role is to provide bulk, or roughage, which supports bowel regularity and accelerates the removal of potentially harmful substances from the digestive tract.1
* Types: Cellulose, lignin, and most hemicelluloses.1
* Sources: Whole grain breads, wheat bran, and vegetables.1

Soluble Fibre

Soluble fibre dissolves or swells in water. While it can slow the transit of food through the gut, it is valued for its ability to help lower blood cholesterol levels.1
* Types: Pectins, gums, mucilages, and some hemicelluloses.1
* Sources: Fruits (such as apples and citrus), oats, barley, and legumes.1

Both forms of fibre help delay glucose absorption, promoting a more stable supply of blood glucose.1