healthful effects of dietary fiber: part 2 (preventing cardiovascular disease)

Micrograph of a heart with fibrosis (yellow) andamyloidosis (brown)
Source: en.wikipedia.org

It is known that populations who consume foods that are not pure, have lower cholesterol levels in the blood plasma. In this population there are also differences in the consumption of dietary fiber, as well as the consumption of other food components such as fats, proteins and carbohydrates, are also significantly different. Nonetheless, much evidence suggests that dietary fiber plays in lowering cholesterol levels specifically in the blood. Several studies using experimental animals and humans reported some dietary fiber components role in lowering cholesterol in blood serum.

The theory most widely accepted by scientists, that some components of dietary fiber is able to bind bile salts, thus preventing re-absorption from the gut, as well as increasing its excretion in the feces. This led to increased conversion of cholesterol from the blood serum into bile salts in the liver.

Not all dietary fiber have the same effectiveness in lowering cholesterol levels. Purified cellulose and wheat bran barely have the ability to lower serum cholesterol levels. However, alfalfa and oats fiber components are very effective in lowering serum cholesterol levels. Other fibers are shown to be effective in lowering cholesterol levels is pectin and gum.

Several studies have reported that physiologically, soluble dietary fiber (SDF) is more effective in reducing plasma cholesterol, also called low-density lipoprotein (LDL), and increased levels of high density lipoprotein (HDL). SDF is also beneficial for people with diabetes mellitus with its function as a reducing glucose absorption in the intestine. Another benefit of the SDF is to make the stomach feel full faster, so it is useful to maintain a normal weight.

The IDF is not very significant as a hypocholesterolemic agent, but a very important role in the prevention of gastrointestinal dysfunction such as constipation, haemoroid, colon cancer, infection appendicitis, diverticulosis, and colitis.

healthful effects of dietary fiber: part 1 (preventing colon cancer)

African inland residents have fewer incidences of illness due to consuming a lot of dietary fiber compared with the population in developed countries. Consumption of dietary fiber in large quantities will provide the body's defense against the onset of various diseases such as colon cancer, diverticular disease, cardiovascular disease and obesity.

colon cancer. source: en.wikipedia.org

Colon cancer 
The relationship between dietary fiber with the onset of colon cancer has received great attention, especially in developed countries. Hypotheses about the relationship between dietary fiber intake by decreasing the incidence of onset of colon cancer can be tested from the following example. In the United States, consumption of meat, poultry and fish have increased rapidly, but instead the consumption of food rich in fiber such as potatoes and of whole cereals has declined drastically. Also turns out the consumption of whole cereals has declined sharply as that is consumed is the flour (which has been purified from the fiber).

Specific components of the diet may be a carcinogen, or intestinal microflora can react on food residues to the gut and turn it into a carcinogenic compound. These compounds when in contact with the cells of the colon mokusa over a period of time, will lead to the growth of cancer cells.

Many hypotheses put forward regarding the mechanism of dietary fiber in the prevention of colon cancer.

First, the possibility of dietary fiber can affect intestinal microflora such that no carcinogenic compounds formed.

Second, dietary fiber is able to bind water, thereby increasing the water content in the large intestine, which causes the concentration of carcinogenic compounds is low and no longer effective to kill cancer cells.

Third, dietary fiber can speed up the transit time of food residues in the colon, so that there is not enough time for carcinogenic compounds to make contact with the cells of the intestinal mucosa.