What is Fiber?

Dietary fiber is a complex carbohydrate and is the part of the plant material that cannot be digested and absorbed in the bloodstream.

The Importance of Dietary Fiber

Fiber (also called roughage or bulk) promotes the wavelike contractions that keep food moving through the intestine. Also, high-fiber foods expand the inside walls of the colon. This eases the passage of waste. Fibrous substances pass through the intestine undigested. They also absorb many times their weight in water, resulting in softer, bulkier stools, that passes through the bowel easily and quickly. Because of this action, some digestive tract disorders may be avoided, halted, or even reversed simply by following a high-fiber diet. A softer, larger stool helps prevent constipation and straining. This can help avoid or relieve hemorrhoids and fissures. More bulk means less pressure in the colon, which is important in the treatment of irritable bowel syndrome and diverticulosis (defects in the weakened walls of the colon). In addition, fiber appears to be important in treating diabetes, elevated cholesterol, colon polyps, and cancer of the colon.

How much fiber should I eat?

Adults should eat 20 to 35 grams of dietary fiber per day. You can meet this goal by eating a well-balanced diet containing a variety of foods such as two servings of fruits, three servings of vegetables, and three or more servings of whole-grain breads or cereals. You may also benefit from a fiber supplement, such as Metamucil or Benefiber. Remember to increase the dietary fiber in your diet gradually to avoid bloating and gassiness, and to drink plenty of fluid (8 cups per day) to avoid constipation.

High Fiber Foods

Fruits & VegetableServing SizeFiber
Raspberries1 cup9
Figs, dried109
Pears, with skin15
Blackberries3/4 cup7
Green peas, cooked1/2 cup4
Prunes3 medium4
Blueberries3/4 cup4
Turnip greens, parsnips, zucchini, or carrots – cooked1/2 cup3
Corn1/2 cup3
Potato, with skin1 medium3
Apple, with skin1 medium3
Orange or banana1 medium2
Spinach, broccoli, green beans1/2 cup2
Grains and Breads Serving Size Fiber
Oat bran muffin15
Graham crackers3 squares4
Barley, uncooked2 T3
Whole-wheat English muffin1 whole3
Whole-wheat pancakes23
Brown rice, cooked1/2 cup2
Whole-wheat bread1 slice2
Cooked Legumes Serving Size Fiber
Chickpeas (Garbanzo)1/3 cup10
Black-eyed peas1/3 cup8
Baked beans1/3 cup5
Pinto, kidney, black or lima beans1/3 cup4
Cereals (1 ounce serving = 1/2 – 3/4 cup)   Fiber
General Mills Fiber One® 12
Kellogg’s All-Bran® 9
Ralston Bran Chex® 5
Post and Kellogg’s Bran Flakes® 4
Nabisco Shredded Wheat and Bran® 4
Bran Flakes 4
Quaker Instant Oatmeal® 3
General Mills Wheaties® 3