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What is Dietary Fiber? Benefits

According to Institute of Medicine at the National Academy of Sciences proposed definition, dietary fiber consists of non-digestible carbohydrates and lignin that are intrinsic and intact in plants

Dietary fiber is found only in plant foods. There is no dietary fiber in meat, poultry, fish or dairy products. The fiber is not broken down by digestive enzymes. It helps the food move through the digestive tracks and expelled out as stool. Part of it may be metabolized by bacteria in the lower gut.

Benefits

Dietary fiber helps fight against heart disease, colon cancer, diabetes, and obesity. High fiber foods help support bowel regularity; and maintain normal levels of cholesterol, blood sugar level, and normal body weight.
Fiber deficient diet may cause constipation, hemorrhoids, diverticulitis, Irritable bowl syndrome, overweight & obesity, diabetes, colon cancer, high blood sugar levels, and high cholesterol levels.

Types of Fiber

There are two types of fiber, soluble and insoluble.

Soluble Fiber

Soluble fiber includes pectin ( Apples, strawberries and citrus fruits), gums (oatmeal barley and legumes) and mucilage (flax seeds). Soluble fiber slows the passage of food through the intestines but do nothing to increase fecal bulk. Soluble fiber lowers blood cholesterol, and helps with constipation.

Insoluble Fiber

Insoluble fiber includes cellulose (bran, legumes, peas, root vegetables, cabbage, covering of seeds and apples), hemicelluloses (bran and whole grains) and lignin (root vegetable, wheat, fruits, and edible seeds flax seed).

Insoluble fiber adds bulk to stool, and absorbs water from the colon to make it softer. In essence Insoluble fiber prevents constipation and associated problems such as hemorrhoids. Insoluble fiber may reduce the absorption of several minerals including Calcium and Iron.

Resistant starch

Resistant starch, acts similar to fiber. Resistant starch is about 10% of the starchy food that can't be broken down and digested. Sources of resistant starch are whole grains, starchy vegetables and fruits such as bananas, potatoes and lentils.