Dietary Fibre

• The human intestines function to complete the process of digestion and absorb digested products into the bloodstream
• The large intestine absorbs water and dissolved minerals (ions) from the indigestible food residues
• Dietary fibre, or roughage, is the indigestible portion of food derived principally from plants and fungi (cellulose, chitin, etc.)
• The small intestine absorbs usable food substances such as monosaccharides, amino acids, fatty acids, vitamins, etc.
• Humans lack the necessary enzymes to break down certain plant matter, like cellulose
• Roughage provides bulk in the intestines to help keep materials moving through the gut
• Roughage also absorbs water, which keeps bowel movements soft and easy to pass
• Ruminants (certain herbivores) possess helpful bacteria in the digestive tract that can break down indigestible plant matter
• The rate of transit of materials through the large intestine is positively correlated with their fibre content
• Health benefits of diets rich in dietary fibre include: reducing constipation, lowering the risk of colon and rectal cancer, lowering blood cholesterol, regulating blood sugar levels, aiding in weight management
• Materials not absorbed by the small and large intestines are egested from the body as faeces
• A large portion of human faeces consists of dietary fibre, such as cellulose and lignin
• Also present in faeces are the remains of intestinal epithelial cells, bile pigments, and human flora (intestinal bacteria)
• Summary of egested materials: BELCH (Bile pigments, Epithelial cells, Lignin, Cellulose, Human flora)