There are various components or nutrients found in plant foods that are beneficial to a person’s health. Typically, these benefits are the result of those ingredients that are eaten, absorbed and used by the body to function properly. For instance, vitamins and minerals, fats, proteins and calories (energy) are absorbed from foods and enable the organs to function and sustain life.

Fiber, also referred to as dietary fiber, differs from other nutrients in that it is not absorbed by the body, passing instead through the entire digestive system largely intact. However, fiber is an important dietary component that can help contribute to good health, especially that of the digestive system. A fiber-rich diet full of whole grains, beans, vegetables and fruits is naturally low in cholesterol, salt and fat and rich in vitamins, minerals and antioxidants (substances that protect against cancer-causing agents).

The various health benefits of dietary fiber can be partially explained by its ability to dissolve in liquids. For example, soluble fiber forms a gel when mixed in a liquid. The viscosity (a measure of a fluid’s resistance to flow) of soluble fiber in some foods has been credited with its cholesterol-lowering effect. After a meal, bile acids rich in cholesterol are secreted into the intestines and mix with the food to help in digestion and absorption. As food is absorbed, the remaining viscous soluble fiber interferes with the reabsorption of these cholesterol-rich bile acids from the intestines. The end result is that the cholesterol is removed from the body and blood cholesterol levels are reduced.

Dietary fiber has an added benefit of being good for the alimentary canal. It adds bulk to and softens the stool, facilitating its exit through the rectum. Constipation is a common problem, especially among the elderly. A high-fiber diet can help relieve constipation and promote regular bowel movements. Alternately, because fiber also absorbs water, it can help solidify the stool of patients experiencing diarrhea.

Fiber can also reduce the risk of diverticulosis – a condition in which small pockets form in the colon – and the inflammation of these pockets which leads to diverticulitis (both conditions are known as diverticular disease). In fact, psyllium seed husk, a good source of soluble fiber, is often used in nutritional supplements and in certain bulking agents (laxatives). It is important to drink plenty of liquids while eating foods that are very high in soluble fiber, especially psyllium seed husk. A diet rich in fiber can also help prevent other digestive disorders including hemorrhoids, irritable bowel syndrome, gallstones and colorectal cancer. 

Because dietary fiber can slow the movement and absorption of foods from the intestines, it also has a favorable effect on blood sugar (glucose) levels after eating. Research also indicates that a high-fiber diet can reduce insulin (a hormone that lowers levels of glucose in the blood) requirements and increase insulin resistance. This improves blood sugar levels and decreases a person’s risk of diabetes. The secondary benefits of a high-fiber diet to reduce the risk of chronic illnesses may include its lower calorie (energy), fat and simple carbohydrate content, which aid in weight management