Nutritional and health benefits of dietary fibre - The Guardian (Nigeria) Newspapers.

Thursday, 19 September 2013 00:00 BY PAUL JOSEPH NANNA Features - Natural Health

AS recent as the 1970s certain diseases that were common among the Caucasians and Americans were almost non-existent in Africa. These diseases include intestinal disorders such as constipation, haemorrhoids, appendicitis, polyps, diverticulitis, and diverticulosis and colon cancer. Others are cardiovascular diseases like hypertension, heart attack, stroke and metabolic conditions such as diabetes.
  A group of researchers led by Dr. Denis Buckitt found that the reason this was so had to do with the diet of the African. The diet of the African was in the main made up of unrefined carbohydrates and other high-fibre foods such as raw vegetables as against the high level of refined, processed and canned foods that the Caucasians ate. They also discovered that the advent of these diseases in Europe and the Americas coincided with the introduction of techniques of converting whole wheat to white flour in the late 1800s. This involved the removal of fibre from the wheat to produce white flour.
  The attraction was the whiteness of the flour, not thinking about the hazards of such a product to our health. Not only that, rice is polished by eliminating the fibre, also to make it look whiter. In the last 40 years or so, not only have these processing plants been established all over Africa, the finished products such as white flour and rice are imported into our continent in large quantities.
What is this dietary fibre?
What first comes to mind when you hear the name, dietary fibre is, this is a fibrous kind of substance. The name is actually a misnomer in that this fibre has nothing to do with fibrous tissue.
  According to the Food and Nutrition Board of the Institute of Medicine in Washington DC, dietary fibre consists of non-digestible carbohydrates and lignin that are intrinsic and intact in plants.
  Functional fiber consists of isolated, non-digestible carbohydrates that have beneficial physiological effects in humans. Total fibre is the sum of both dietary and functional fibres.
  The dietary fiber includes non-starch polysaccharides found in plants, such as cellulose, pectin, gum and hemicellulose. Others are fiber contained in oats and wheat bran, oligosaccharides, lignin and some resistant starch.
  There are two main components of fibre, soluble and insoluble fibre. Soluble fibre can dissolve in water and it is readily fermented in the colon into gases and physiologically active byproducts. This type of fibre slows down the passage of food in the digestive tract. Insoluble fibre, on the other hand, does not dissolve in water. It is metabolically inert and provides what is known as bulking. In bulking, this fibre absorbs water throughout the length of the digestive tract. This produces two distinct and important effects.
  Firstly, they increase the bulk of the stools and secondly, they speed up the passage time of food through the intestines. The end result is that passing out stools becomes easier and more frequent. This is very important in that it is the mechanism by which insoluble fibre cleanses, detoxifies the colon and reduces the acid waste load in the colon. This helps to prevent certain diseases, as we shall see later.
Plant sources of dietary fibre
Dietary fibres are predominantly found in plants. Some plants contain both types of fibre but the decision, whether or not to eat some fibre, should not be based on eating one or the other. In other words, let your decision be based on the fact that the body needs fibre and you are going to supply enough fibre to the body on a daily basis.
  Common sources of both soluble and insoluble fibre include, fruits such as avocado, bananas, pears, apples, prunes, plums, skin of kiwifruit and grapes; vegetables like broccoli, celery, carrots, green beans, cauliflower etc. Other sources are whole grains, wheat and corn bran, oats, rye and barley. A variety of legumes are also high in fibre and in this category are black beans, white beans, kidney beans and lentils. The rest are, almonds, flaxseed, sweet potato, onions, brown rice and Ofada rice.
  Recommended daily intake of fibre for the American adult is 20 to 35 grams but research shows that they have fallen short of this because of the typical American diet. Going by diet, one can safely say that an adult Nigerian should be doing more that 50 per cent of this daily requirement. I am certain that we can do even better than this if we add a few of those foods that have a high content of fibre to our meals daily.
  Next week Thursday, I shall continue on this topic as I present the beneficial effects of fibre on conditions such as heart disease, diabetes, cholesterol metabolism, colon health and obesity.
God bless.