Plant foods – cereal, grains, vegetables, nuts, fruit and legumes are sources of DIETARY FIBRE. Animal foods ie meat, eggs, fish and milk and sugar contain no fibre. Health authorities advocate today, a moderate increase in DIETARY FIBRE intake as it has been proven to maintain the regular functioning of the human bowel, reduce cholesterol levels by binding to cholesterol in the bowel, provide a mucilage-type healing coating to the bowel wall, absorb poisonous toxins and metabolic wastes and reduce the incidence of formation of pre-cancerous polyps and growths in the colon.
DIETARY FIBRE consists of two categories – soluble or insoluble. Examples of soluble fibre are the pectin in apples and carrots (used by Grandma to set her jams and effective in binding up diarrhoea) and the gummy fibre in oat bran. Insoluble fibre consists of those plant components that are not digested by enzymes of the gastro-intestinal tract and pass through the bowel unabsorbed ie wheatbran, barley bran, rice bran, guar gum and psyllium.
Foods containing fibre take longer to chew and provide bulk and satisfaction hence their use in weight control programs. Fibre absorbs water into itself, guar gum may be ingested half an hour before meals along with a glass of water. As it absorbs the water it swells, so inducing a feeling of fullness prior to eating.
Fibre in the bowel absorbs water into itself too, swelling and providing a bulking, softening effect, causing pressure receptor cells in the bowel wall to register fullness of the bowel which then initiates more regular, easier defecation. For this reason fibre such as Psyllium may be successfully used in conjunction with a daily intake of one and a half to two litres of water in correcting tendencies toward constipation and diverticulitis.
Excesive consumption of bran or wholegrain cereals is not recommended because of the capacity of phytic acid (in seeds) and DIETARY FIBRE to bind up essential minerals. Rickets, zinc deficiency dwarfism and iron deficiency anemia have been related to a high consumption of bran and wholemeal breads. The recommended daily intake of fibre is 25 -35 grams. Excessive intake will cause stomach bloating and discomfort and flatulence.