On Fiber

This is a guest post by Melissa Marek, RD LD

Fiber is an extremely important part of your daily diet. Its best known benefit is its ability to help keep our bowels moving. Eating enough fiber will help prevent constipation. The added benefit is that it also plays a role in protecting against diseases such as diabetes, heart disease and cancer. If that isn’t enough reason to get a daily dose of fiber, it also helps with weight management by helping to keep you fuller longer.

In order to make sure you are getting enough fiber, it helps to understand where it comes from and where you can find it. Fiber comes mainly from plant cell walls, the parts that cannot be digested by the enzymes of the GI tract. For that reason, fiber can be found in plant foods such as fruits, vegetables, and grains.

To best benefit from fiber, the recommended daily amount is 21-25 grams per day for women and 30-38 grams per day for men. This is not a difficult goal to meet, but remember that when adding fiber to your diet, you will need to increase your fiber intake slowly and more importantly, increase your fluids. If you don’t drink enough fluids you may suffer from constipation, the very thing that fiber helps alleviate.

To better comprehend the benefits of fiber and how to best meet daily requirements, it helps to understand that there are different types of fiber. They come from different sources and, accordingly, help with different things.

SOLUBLE FIBER may help lower blood cholesterol, especially LDL (bad) cholesterol. It also helps control blood sugar in people with diabetes. You can get soluble fiber from oats, oat bran, dried beans and peas, nuts, barley, flax seed, oranges, apples, carrots, and psyllium husk.

INSOLUBLE FIBER moves bulk through the intestines, which helps prevent constipation. It also controls and balances the pH in your intestines. Insoluble fiber can be found in fruit skins, root vegetable skins, dark green leafy vegetables, whole wheat products, corn bran, seeds and nuts.

Soluble fiber, as it name alludes, becomes a jelly-like mass when mixed with water and ferments in the intestinal tract, but insoluble fiber just absorbs the water and bulks up stool.

The term DIETARY FIBER, which appears on nutrition facts labels is merely a sum of the soluble and insoluble fiber content in a product, per serving.

A common source of fiber is whole grain. Whole grain refers to the entire grain seed (bran, germ, & endosperm).  Whole grain foods are an important source of not only fiber, but also of vitamins, minerals and other health-promoting compounds that you won’t find in a refined grain.


According to the 2005 Dietary Guidelines for Americans, 3 or more ounce-equivalents of whole grain products per day is ideal. You can meet this requirement by adding barley, buckwheat, bulgur, corn, millet, rice, rye, oats, sorghum, wheat and wild rice to your daily diet.

What does a one-ounce equivalent of whole grains look like?

  • 1 slice 100% whole grain bread
  • 1/2 of a 100% whole grain English muffin or bagel
  • ½ cup hot cooked oatmeal (Rolled oats or quick oats)
  • 2 cups popped popcorn
  • 1 ounce baked tortilla chips (About 15 chips)
  • 1/3 cup cooked whole wheat pasta
  • 1/3 cup cooked brown rice, bulgur, sorghum, or barley



  • Sprinkle flax meal, wheat germ,  or nuts/seeds onto your cereal, cottage cheese, yogurt, or even frozen yogurt
  • Add fresh or dried fruits to your cereal or yogurt
  • Substitute whole wheat flour for at least 1/3 of the all purpose flour in baked goods
  • Add frozen vegetables to soups or casseroles
  • Add beans into a salad, soup, or stew
  • Cut prunes into pieces and mix them into yogurt, cereal, or pancake mix

What to do at the supermarket:

Packaging for fiber rich foods now often contain a label promoting its fiber content. These labels make finding fiber-rich foods easy so shoppers don’t have to go through the hassle of checking out the food label or searching for the fiber content. But what do these regulated fiber claims mean exactly?

  • 100% Whole Grain or 100% Whole Wheat: The product doesn’t have any refined white flour
  • Good source of fiber:  There are at least 3g per serving
  • Excellent source of fiber:  There are at least 5g per serving
  • When reading the ingredient statement, a whole grain should be listed FIRST!

Here’s a handy list of fiber rich products:

  • Oats
  • Oat bran
  • Grains (Barley, bulgur, Kasha, Amaranth, Quinoa, Couscous)
  • Polenta
  • Brown rice
  • Whole wheat breads and pastas
  • Fresh fruits (Oranges, pears, dried figs, apples, berries, raisins)
    —> Choose whole fruits (fresh, frozen, or dried) over juices, which have most of the fiber removed
  • Fresh vegetables (Winter squash, peas, eggplant, beets, cabbage, broccoli, artichoke hearts, corn)
  • Potatoes & sweet potatoes
  • Dried beans
  • Nuts

Melissa Marek is a graduate of Texas A&M University with degrees in both Nutritional Sciences and Food Science & Technology.  She has experience with recipe analysis for magazines and restaurants as well as with nutrition facts labeling for large corporations and private label companies. She is a registered dietitian at Axxya Systems, makers of Diet Analysis and Food Labeling software products. Contact her at mmarek [at] axxya [dot] com.

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  • http://www.foodinsight.org Elizabeth Rahavi

    Great blog post on the benefits of fiber, and since it is National Fiber Focus month it comes with good timing. Others may be interested in our in-depth fact sheet on fiber and other resources: http://www.foodinsight.org/Resources/Detail.aspx?topic=Fiber_Fact_Sheet.

    Elizabeth Rahavi, RD, Associate Director, Health and Wellness at the International Food Information Council Foundation

  • http://www.kitchenmonki.com Kitchen Monki Dan

    thanks for this excellent, informative post! will share this with our fb fans. Cheers!

  • http://www.alzheimersreadingroom.com Bob

    Bowel movement in persons suffering from Alzheimer’s disease is a big problem. Do you have any specific recommendations for that population?

    Bob DeMarco
    Alzheimer’s Reading Room

  • Tom

    Thanks for taking the time to contribute this informative article.
    I recently had open heart surgery and can’t tolerate the statin drugs. So I was especially glad to see the part about soluble fiber helping to lower LDL cholesterol.

  • Maggie

    How many points should a average person eat a day?