Doctors have known for decades that fiber is the foundation of any healthy diet, and can help reduce the risk of cancer, heart disease and diabetes. More recent research, however, shows that while fiber is good, not all fiber is the same. Other insoluble fiber, found in wheat bran, seeds, whole grains, and the skins of vegetables and fruits, is also good but serves a different purpose. Most nutritionists say their primary goal is to encourage people to increase their total fiber intake, regardless of the specific type. The American diet, rich in processed and fast foods, provides only 12 to 14 grams of fiber per day, about half the recommended amount.
Soluble fiber remains longer in the intestines and thus absorbs more cholesterol.
Insoluble fiber absorbs water, which increases the speed at which waste passes through the body. Both types of fiber serve an important function in the body, but to reduce the risk of heart disease, it's worthwhile to note the difference. Adding a bowl of oatmeal and a bowl of split pea or black bean soup is a good way to start adding soluble fiber to the diet. But it's only part of the story. A good rule of thumb, courtesy of the American Dietetic Association, is five servings or fruits and vegetables daily, and legumes at least once or twice a week.