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(Lesson 10) Dietary Fiber


Dietary Fiber

Let's talk about what we will cover in this lesson.  Did you know that there is something in food that helps with digestion and offers other health benefits as well? It's called dietary fiber. In this lesson, we will learn what dietary fiber is, what foods are good sources, what the health benefits are, how much dietary fiber we need, and tasty ways of getting more fiber into our diets.

What You Will Learn

  • The different types of dietary fiber (soluble and insoluble) and the benefits of each
  • Medical problems that can result from too little dietary fiber
  • What foods and food groups are good sources of dietary fiber
  • The amount of dietary fiber recommended each day


The U. S. Department of Agriculture (USDA) developed a tool called MyPlate to help you see what foods you and your family should eat each day for good health.  MyPlate can be found at the following website:  www.choosemyplate.gov.  Foods that make similar nutritional contributions are grouped into five basic food groups - fruits, vegetables, grains, protein, and dairy. On the website, you can get a personalized daily food plan that tells you how many servings of each food group you need each day.

For good health, you should eat the number of servings recommended for you from each of the basic food groups.


Go to Daily Food Plan on the ChooseMyplate website.  Find out how many servings of each food group you need each day.  Try it out for each of your family members also.

Question 1:

What is dietary fiber?

Dietary fiber is the non-digestible part of plants that adds bulk to your diet. It is found only in foods that come from plants. Fiber is found mainly in the cell walls, providing the structure and shape of the plant. Fiber gives celery its rigid stalk and gives turnip greens the strong stem that holds up its leaves. Fiber is the part of whole grains, fruits, vegetables, beans, nuts and seeds that we cannot digest. Since it can't be digested and absorbed in our body, fiber is really not a nutrient. It's a non-nutrient part of plant foods.

Question 2:

What are the types of dietary fiber?

There are two kinds of dietary fiber. They are not alike and they keep you healthy in different ways. Fiber is grouped as being either water soluble or insoluble. Water soluble fiber dissolves in liquid and forms a gel-like substance; insoluble fiber stays intact as it moves through the digestive track. You need to eat foods that give you both kinds of fiber. 

It's your Turn:

  • Write down the names of two kinds of dietary fiber and what they mean.
  • Tell someone why it is important to drink plenty of water and other fluids along with fiber consumption.

 A high-fiber diet has many benefits, which include:
  • Normalizes bowel movements.  Dietary fiber increases the size and weight of stool and softens it.  A bulky stool is easier to pass and reduces the chance of constipation. When increasing fiber intake, be sure to increase your water intake. Without water, the stool becomes drier and difficult to eliminate. Fiber may also help to solidify loose, watery stools because it absorbs water and adds bulk to stool. 
  • Helps maintain bowel health and integrity.  A high-fiber diet may lower your risk of developing hemorrhoids and small pouches in your colon or diverticular disease. 
  • Lowers blood cholesterol levels.  Soluble fiber, which is found in beans, oats and oat bran, and flax seed, may help lower total blood cholesterol levels. It absorbs LDL or "bad" cholesterol and is removed through the stool.
  • Helps control blood glucose levels.  Fiber, particularly soluble fiber, can slow the absorption of glucose and can improve blood glucose levels.  This can help people with diabetes control their blood glucose levels.  A diet high in insoluble fiber has been shown to help reduce the risk of developing type 2 diabetes.
  • Aids in weight loss.  High-fiber meals tend to linger longer so you stay full longer.  Because dietary fiber is not digested or absorbed, high-fiber diets are less "energy dense," which means they have fewer calories for the same volume of food.


Insoluble fiber doesn't dissolve in water.

Have you ever had trouble with constipation or hemorrhoids?  If so, you need more insoluble fiber (fiber that does not dissolve in water) and water in your diet. Insoluble fiber helps prevent painful constipation and hemorrhoid problems.

Water insoluble fiber refers to the rigid material that gives structure to the leaves, stems and seeds of plants. It is also called roughage.  Broccoli, celery, turnip greens and other leafy green vegetables, okra, carrots, squash, and wheat would be examples of plant foods that give us insoluble fiber.  The insoluble fiber in these plant foods gives structure to plant leaves, stems and seeds.

Insoluble fiber is concentrated in the protective outer layers of whole grains, called the bran layers. Wheat bran, bran, whole-grain cereals and cereal products are excellent sources of insoluble fiber. Select cereals that have the word bran in their names for the best sources of bran.

Insoluble fiber is also concentrated in stalks, seeds, and skins or peelings of fruits and vegetables. Examples include skins of apples, pumpkin or sunflower seeds, and celery stalks.

Insoluble fiber is most often found in whole-grain products such as whole-wheat bread. Wheat bran seems to be one of the most effective stool-softening fibers. When eating foods that are good sources of water insoluble fiber, drink plenty of water and other fluids. This increases bulk, frequency and ease of bowel movements. Insoluble fiber tends to speed the movement of the solid wastes through the lower part of the intestinal tract, increasing the frequency of bowel movements. If you don't have regular bowel movements or if you may go days without having a bowel movement, you need to include more insoluble fiber and water in your food intake. Insoluble fiber also helps to satisfy your appetite by creating a full feeling.

Soluble fiber dissolves in water and is broken down by bacteria in your colon.

It is found in dry beans and peas, in some cereals such as oats and barley, and in some fruits and vegetables. Water-soluble fiber such as oat bran, oatmeal and the fiber of apples helps lower blood cholesterol levels and helps regulate the body's use of sugar.

Visit the Quaker Oats Canada Web site to see ways of getting more water soluble fiber from oats into your diet:

Click on the Cooking & Recipes tab.  Click on the Recipe Finder to find different recipes with oats.  Note that the recipes include metric as well as standard measurements.

Review of MyPlate

What foods give us fiber, plant or animal foods or both plant and animal foods?

Which food groups are good sources of dietary fiber?

Where in MyPlate are they located?

How many servings do you need each day?

We obtain dietary fiber from plant foods. The best sources of dietary fiber are vegetables, fruits, whole grains, such as whole grain breads and cereals, and nuts and seeds.

We need to eat a variety of foods as recommended by the USDA's 2010 Dietary Guidelines for Americans (DGA) and MyPlate, including foods that are good sources of complex carbohydrates and fiber. The DGA recommends that we make at least half our grains whole. This includes whole-grain bread, cereal, pasta and rice. A study of 30,000 women ages 55 to 60 found that they were 30 percent less likely to die of a heart attack if they ate at least three servings of whole-grain breads and cereals instead of refined grain foods. Americans eat only 5 percent of grain foods as whole-grain foods.

We need to increase complex carbohydrate and high fiber foods in our diets:

  • Make at least half of your plate fruits and vegetables
  • Make at least half your grains whole. 


How much dietary fiber do you need?

The National Cancer Institute recommends 20 to 30 grams of dietary fiber per day with an upper limit of 35 grams. The percent Daily Value for dietary fiber on the nutrition label is based on 12 1/2 grams of dietary fiber per 1,000 calories or 25 grams of fiber for a 2,000 calorie diet.

It is important to increase fiber intake gradually. This will give the intestinal tract time to adjust. Also, increase water intake when increasing fiber to prevent hard stools that are difficulty to eliminate.

Last Updated: 9/23/2015 7:49:19 AM
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