Dietary fiber includes the nondigestible carbohydrates. These may be either water soluble or water insoluble. Both have nutritional significance.
The water insoluble group that includes wheat products and wheat bran is believed to reduce chances of colon cancer by increasing bulk and diluting the effect of secondary bile acids.
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While claims may be made for cholesterol-level-lowering properties of brans from different grains (e.g., the bran from oats and the bran from the psyllium seed, which have much higher amounts of bran than that of other grains), the more productive course for trying to control cholesterol levels is to limit the consumption of foods that are high in cholesterol and high in fats.
The consumptions of fiber is recommended, although not to excess. It appears that excessive amounts of dietary fiber may interfere with the retention of minerals required by the body.
Fibers