Explain the Solubility in Water of dietary fibre?

Fibres that dissolve in hot water are soluble and those that do not, are insoluble. Several structural features affect solubility. We shall not go into the details of these features since it is not within the purview of this course, we will however, study the functions of soluble and insoluble DF.

Generally soluble fibre:

• Delays gastric emptying;
• Increases the transit time (slower movement) through the intestine; and
• Decreases nutrient absorption (glucose).

Insoluble fibre:

• Decreases (speed up) intestinal transit time, and
• Increases faecal bulk.