Health-related components of cereal grains

There is a vast literature on cereal components that have been shown to give health benefits. The main ones will be briefly summarized. 

One of the problems highlighted in recent times is the importance of fiber in the diet. Normal starch is rapidly broken down into simple sugars by enzymes (amylases) in the human body. A high consumption of starch can lead to spikes in blood sugar level. The rate and extent of this rise are measured by the glycemic index. To avoid sharp fluctuations, which are thought to be damaging to health, inclusion of a certain amount of fiber in the diet is recommended. 

Insoluble fibers include the polysaccharides cellulose and hemicellu-lose. They facilitate the movement of waste through the digestive tract. Examples of soluble fibers are the p-glucans—also polysaccharides—that have attracted a good deal of attention due to the claim that they lower blood cholesterol levels. Beta-glucans are found in most cereals and occur at relatively high levels in the bran of oats and barley (See Chapter 13). 

Resistant starch has also generated interest in recent times. This is starch that escapes digestion in the small intestine of healthy individuals and passes through the large intestine, where it acts like dietary fiber. Resistant starches have been classified into four main groups  

physically inaccessible starch, as found in unprocessed whole grain 

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