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Fiber is a vital component in the everyday diet.Fiber sources

However, the average American diet is very low in fiber or roughage because of the increasing refinement and processing of fruits, vegetables and grains.  Fiber plays an important part in helping maintain good health and although it isn’t a nutrient, fiber is recognized by most physicians and scientists as vital to everyone’s diet – increasing bulk in our diet without adding calories.  Therefore, increasing dietary fiber should be part of a lifelong pattern.


What is Fiber?

Fiber is the structured part of plants.  It is the framework that supports and holds the plants together as it forms the skeleton of all plants and provides their protective outer coating of shell or husk.  Fiber is sometimes called bulk or roughage.  Fiber is a strand like material that cannot be digested by the human stomach because it is resistant to breakdown by digestive enzymes.  However, it can be partially digested by some bacteria in the lower intestines.


Where is Fiber found?

Fiber is found in only plant foods such as fruits, vegetables, beans and greens. Plants contain different kinds and amounts of fiber depending on species, the variety, growing conditions, age of the plant when harvested and the degree to which it is processed.

The amount of fiber contained in food is often expressed as “crude fiber”.  This is a scientific measurement of the organic material left after chemical digestion of food in laboratory studies.  But, because this laboratory process digests more than the natural chemical digestion that occurs in the body, most experts prefer to use the term “total dietary fiber”, which is usually two or three times higher than “crude fiber”

Food lists give the percentage of total dietary fiber per 100 grams (or 3 ½ ounces).  Any food that contains 6 or more percent fiber is considered to be a high fiber food.


What can Fiber do for health?

There are many benefits of fiber that are well established.  Of particular benefit is its value in aiding in the elimination and treatment of constipation.  With enough fiber, bowel movements are larger and softer.  Laxatives are not necessary if there is enough fiber in the diet.

Fiber is also generally accepted as factor in lowering the risk of divericula and hemorrhoids.  There is growing evidence that fiber in the diet may protect against diabetes, heart attacks, strokes and colon cancer.

It has been found that high fiber diets aid in better control of blood sugar responses in diabetic patients and in lowering blood fats such as cholesterol and triglycerides. These diets have been found useful for weight loss because they are filling but also low in calories.


How does Fiber work?

Fiber has earned the title of “nature’s broom” because it helps to sweep the products of digestion through the body and eliminate them.  It absorbs moisture, consequently adding bulk to food materials as they pass  through the intestinal tract.  Bulk stimulates intestinal musculature, helping waste products to quickly move along the intestinal tract and to be eliminated regularly, thus reducing strain on blood vessels and lower bowel.

Fiber is a proven aid to dieters.  It tends to satisfy hunger without providing calories, by swelling up in the body and creating a sense of fullness.

On the negative side, fiber also absorbs significant amounts of zinc and iron, thereby reducing the percentage of assimilation of these important nutrients in the body.

One point to keep in mind is that plant fiber, cellulose, is not broken down in the digestive process.  There is no enzyme that aids in the digestion of cellulose.  Therefore, fiber requires chewing and it is important that the cellulose is broken into tiny pieces by chewing each bite extremely well.  It this isn’t done, cellulose can lead to bloating and gas.

If a high fiber diet is instituted, alcohol should be avoided until the diet has its full effect.


How much Fiber should be included in the daily diet?

Moderation is key to the healthful use of fiber.  It is important to remember that fiber is not a cure for all. Adding fiber to an unbalanced diet will do little or no good.  Fiber should form just one important part of a balanced diet chosen from a variety of wholesome foods.


What is the recommended way to improve daily Fiber intake?

One should gradually increase high fiber foods while decreasing the amount of refined sugars and animal fats. In order to benefit from all types of fiber, one should eat a wide variety of foods and remember it is essential to drink liquids.

Here are some foods especially high in fiber.  Include some of these at each of you meals throughout the day.

  • Fruit- Those fruits with edible skin and/or seeds are highest in fiber.  To get the most fiber, eat apples and pears with skin, orange and grapefruit sections and berries.
  • Vegetable- As with fruits, vegetables with edible skin or seeds are highest in fiber.  Raw and crisp- cooked vegetables are the best.  Some high fiber vegetables include broccoli, brussel sprouts, peas, acorn squash and baked potato with skin.
  • Bread and Cereals- Bran cereals and whole grain breads are high in fiber.  Unprocessed bran or wheat germ can be added to many foods such as: juice, hot cereal, applesauce and salads.
  • Beans and Legumes-  Protein- rich beans and legumes such as baked beans, navy beans, pinto beans, lima beans, soybeans, dried peas and lentils are excellent sources of fiber on contrast to the protein-rich foods from animal origin.
  • SnacksNuts, seeds and raw vegetables are nutritious snacks and a good source of fiber.

In addition to modifying the type of food selected, recipes can be made higher in fiber. For example: using whole grain flour instead of white flour, adding bran or wheat germ to meatloaf, nuts and seeds to cookies and cakes, and beans, legumes and vegetables to soups and stews.

Increasing the fiber in your diet can be easy.  For example, here is one way of making a “traditional” breakfast high in fiber.


 “Traditional” Breakfast

  • Orange juice
  • Corn flakes
  • White toast
  • Margarine
  • Grape Jelly
  • Milk


High Fiber Breakfast

  • Fresh Orange
  • Bran cereal
  • Whole wheat toast
  • Margarine
  • Strawberry preserve
  • Milk


Is it possible to eat too much fiber?

More harm than good can result from too much fiber in the diet or a sudden switch to a very high fiber diet. Normal digestion needs a period of adjustment to less refined foods; therefore, persons with sensitive digestive tracts can be especially affected by too much fiber.

Not all fibers are equally effective at all functions.  Some forms of fiber, such as bran, are sometimes an effective treatment for constipation.  However, bran, when eaten dry, can have an opposite effect and cause constipation.  It is important to remember to include sufficient liquids to aid in digestion and normal body functioning.

A word of caution: there is a concern among Nutrient Scientist about the adverse effects on the health of individuals who cut back on their consumption of more nutritious foods and fill up on foods containing large amounts of wood cellulose.  One should maintain a well balanced diet selected from a variety of wholesome foods and fiber form an integral part of a balanced diet.


Dietary Fiber

Bulking up your diet can be a healthful decision

A high-fiber diet can help lower cholesterol and may protect you from colon problems such as diverticulosis, irritable bowel syndrome and colon cancer.  It may also help reduce your risk for diabetes.

Aim for 25-30 grams of dietary fiber a day from a variety of sources.  Increase your consumption slowly to avoid digestive upset, and remember to drink plenty of water because without it fiber can be constipating.

Fiber content is often listed on product labels. Here’s the fiber in some common food products.


Breads (1 slice) and Cereals

Bagels (3 ½ inch) 1.6g Kellogg’s Nurti-Grain (3/4 cup) 4.0g
Healthy Choice Hearty 7-grain 3.0g Kellogg’s Corn Flakes (1 cup) 1.0g
Oatmeal Bread 1.1g Kellogg’s All-Bran Extra Fiber (1/2cup) 13.0g
Village Hearth Kid’s Choice White 2.0g General Mills Fiber One (1/2 cup) 13.0g
Whole Light Bread 1.9g General Mills Wheaties (1 cup) 3.0g
Wonder Light bread 3.0g General Mills Cheerios (1 cup) 3.0g
Post 100% Bran (1/3 cup) 8.0g Oatmeal, quick/reg/instant (1 cup cooked) 4.0g
Post Shredded Wheat (2 biscuits) 5.0g Egg noodles, enriched (1 cup cooked) 1.8g
Post Bran Flakes (3/4 cup) 5.0g Rice, brown/cooked (1 cup) 3.5g
Post Fruit & Fiber (1 cup) 5.0g Spaghetti, enriched (1 cup cooked) 2.4g
Kellogg’s raisin Bran (1 cup) 8.0g Tombstone Pizza 12” cheese (1/4 pizza) 3.0g


Fruits and Nuts

Apple, medium with skin 3.7g Orange, Valencia (1 medium) 3.0g
Apple Sauce, unsweetened (1/2 cup) 1.5g Peach, raw (1 medium) 1.7g
Apricots, raw (3 medium) 2.5g Peaches, canned, juice pack (1 cup) 3.2g
Avocado, raw/California (1 medium) 8.5g Peanuts, dry roasted (1 oz) 2.3g
Banana (1 medium) 2.7g Peanut butter, creamy (2 tbsp) 1.9g
Blueberries (1 cup) 3.9g Pears, canned/ juice ( 1 cup) 4.0g
Cashews, oil roasted (18 medium) 1.1g Prunes (10, dried) 6.0g
Cherries, sweet (10 cherries) 1.6g Raisins, seedless (2/3 cup) 4.0g
Dates, dried (10 dates) 6.2g Raspberries, raw (1 cup) 8.4g
Grapefruit, pink & red (1/2 medium) 1.4g Strawberries, raw (1 cup) 3.4g


Vegetables (cooked, unless specified)

B&M Baked Beans Vegetarian (1/2 cup) 7.0g Lettuce, iceberg (5 leaves) 1.5g
Broccoli, boiled (1/2 cup) 2.3g Lima Beans (1/2 cups) 6.6g
Cabbage, red (1/2 shredded0 1.5g Onions, raw (1/2 cup, chopped) 1.4g
Campbell’s Chunky Veg. Soup (1 cup) 4.0g Peas, canned (1/2 cup) 3.5g
Carrots, raw (1 medium) 2.2g Popcorn, air popped (3 ½ cups) 4.2g
Cauliflower (1/2 cup, pieces) 1.7g Potato, boiled w/o skin (1 potato) 2.4g
Celery (1 stalk, raw-7.5”long) 0.7g Spinach (1/2 cup) 2.2g
Corn (1/2 cup) 2.3g Sweet potato (1 baked with skin) 3.4g
Green beans (1/2 cup) 2.0g Tomato, raw (1 tomato) 1.4g
Kidney beans, red/boiled (1 cup) 13.1g V8 100% Vegetable Juice (10 oz) 2.0g


Cooking ingredients & supplements

Citrucel (1 rounded tbsp) 2.0g Metamucil (1 rounded tsp) 3.4g
Fibermed Snacks (15 pieces) 5.0g Oat Bran, uncooked (1/3 cup) 4.8g
Flour, whole wheat (1 cup) 14.6g Perdiem, plain (1 rounded tsp.) 4.0g
Flour, white (1 cup) 3.4g Wheat Bran (1/2 cup) 12.8g


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