Sources of soluble fiber include oatmeal and oat bran, nuts and seeds, fruits, and legumes such as peas and beans. Insoluble fiber comes primarily from whole grains, such as whole wheat bread and cereals, brown rice and vegetables including carrots, cucumbers, celery and tomatoes. The health benefits of these two types of fiber differ. Insoluble fiber increases the movement of material through the digestive system, so it helps to maintain regular bowel movements and avoid constipation. Soluble fiber has been shown to lower cholesterol and help keep blood sugar in a normal range. Let’s look more closely at a few of the medical problems that fiber benefits.

Fiber and constipation

Fiber passes virtually unchanged through the gastrointestinal tract, creating a bulkier stool that is easier to pass. Regular and adequate fiber intake decreases the chances of becoming constipated as well as helping to avoid associated problems such as hemorrhoids or rectal fissures. The fiber in wheat bran and oat bran seems to be particularly effective in helping with this.

Fiber and diverticular disease

In diverticulosis, small pouches in the colon, known as diverticuli, bulge outward through weak spots. A low fiber diet is thought to be the primary cause of diverticulosis. When the pouches become infected or inflamed, the condition is called diverticulitis. Diverticulitis typically causes only abdominal pain, but can also cause life-threatening infections. In the U.S., diverticulosis is estimated to occur in one-third of all of those over age 45 and in two-thirds of those over age 85. In a long-term study, eating adequate amounts of dietary fiber was found to decrease the risk of developing diverticular disease by almost 40%.

Fiber and type 2 diabetes

Type 2 diabetes, also known as “adult onset” diabetes develops when the body cannot produce insulin or properly use the insulin that it produces. For some time now, it has been known that maintaining a healthy weight and being physically active lowers the risk of developing Type 2 diabetes. It now appears that eating a diet high in fiber is linked to a lower risk of developing Type 2 diabetes also.

Fiber and heart disease

High intake of dietary fiber has been linked to a lower risk of heart disease. In a Harvard study of over 40,000 male health professionals, researchers found that a high total dietary fiber intake was linked to a 40% lower risk of coronary heart disease, compared to those with a low fiber intake. This appears to be due to the cholesterol-lowering and diabetes-preventing functions of fiber.

Fiber and weight loss

Eating a high-fiber diet may also help with weight loss as it requires more chewing and promotes hunger satisfaction by giving the stomach a sense of fullness. High-fiber diets tend to be less "energy dense," which means they have fewer calories for the same volume of food.

How much fiber do you need each day?

The National Academy of Sciences' Institute of Medicine has specified the amount of fiber needed to promote optimal health. Men, age 50 and younger, need 38 grams of fiber a day and those age 51 and older need somewhat less at 30 grams. Women, 50 and younger should receive 25 grams of fiber a day and those women age 51 and older need at least 21 grams.

For the amount of fiber in food commonly eaten go to:

http://www.mayoclinic.com/health/high-fiber-foods/NU00582

• Eat at least 4 1/2 cups of fruits and vegetables each day. Fruits and vegetables that are high in fiber include apples, oranges, broccoli, carrots, prunes and figs.
• Replace white bread with whole-grain breads and cereals. Eat brown rice instead of white rice. Eat more of the following foods: bran muffins, pop corn, and oat meal.
• Add 1/4 cup of wheat bran (miller's bran) to foods such as cooked cereal or applesauce or meat loaf.
• Choose whole-grain or bran cereals for breakfast.
• Eat cooked beans each week.