Guidelines for Increasing Dietary Fiber

Fiber is a very important component of a healthy diet. There are several reasons to increase dietary fiber intake. During cancer treatment, pain medications, insufficient water intake, and reduced physical activity all contribute to constipation.  Upon completion of treatment for healthy survivorship, increasing dietary fiber also has a lot of health benefits including reduced risk for colon cancer, lower cholesterol, stable blood sugar, weight loss, and bowel regularity. 

There are two types of fiber found in foods: Soluble Fiber and Insoluble Fiber.

Soluble Fiber is completely digested by the body and aids in reducing cholesterol, stabilizing blood sugar, and getting rid of other toxins present in the gastrointestinal tract. In the case of diarrhea, loose bowel movements, or increased gastrointestinal motility, soluble fiber functions as a bulking agent and slows down the movement of waste through the gastrointestinal tract. Examples of foods that contain soluble fiber include oats, beans, legumes, sweet potatoes, onions, and fruits such as apples, bananas, and pears. The daily goal for soluble fiber is 10-20 grams. 

Insoluble Fiber is not digested by the body and is excreted as waste. This is the type of fiber that promotes bowel regularity and discourages the development of hemorrhoids. Examples of insoluble fiber include wheat bran, nuts, and seeds. The daily goal for insoluble fiber is 15-30 grams.

Total daily fiber intake of soluble and insoluble combined should be at least 30-35 grams.

Here are some tips and suggestions for increasing dietary fiber:

  1.  Be selective when choosing grains.
  • Buy grains in bulk form that are whole and unprocessed. These are usually found in the bulk bins or barrels in the bulk section of the grocery store.
  • Buy only products that are marked with the disclaimer that they are made only with “100% whole grain.”
  • Read the label on grains and make sure that in a 1 cup serving there are between 4 and 14 grams of fiber per cooked cup.
  • Look for “whole wheat flour” or “whole grain flour” as the first ingredient on the package label when selecting bread and bread products.
  1.  Incorporate beans, peas, and lentils regularly into your diet.
  • Beans are an excellent substitute for meat since they are a great source of protein as well as fiber.
  • Add beans as well as other gas forming foods gradually to allow the gastrointestinal tract to adjust and to avoid bloating or discomfort.
  • Soak dried beans or rinse canned beans before cooking to help remove some of the gas-producing starches.
  • Beans contain soluble and insoluble fiber so the benefit of both is found in one food.
  1. Start each day with a high fiber breakfast.
  • Choose a breakfast cereal that contains at least 5 grams of fiber and no more than 10 grams of sugar per serving. 
  • Cereals may contain soluble and insoluble fiber. Oatmeal contains only soluble fiber.
  • Add fresh fruit instead of juice to your breakfast to get the benefit of fiber.
  1. Use half whole wheat flour in recipes that call for white flour.
  • It will change the texture in some recipes. Do not use in recipes that call for cake flour. It will make the product too dense and heavy.
  1. Add a salad to at least one meal each day.
  • Use a variety of leafy greens including romaine, leaf, and spinach.
  • Be creative and top the greens with other high fiber foods including broccoli, beans, raspberries, beets, cucumbers, and celery.
  1. Add a fiber supplement such as psyllium husk to your daily routine.
  • These are found in many products at your local grocery store or pharmacy. 
  • Be sure to drink plenty of water when adding a fiber supplement.
  • Drink these in a timely manner. Once mixed with a liquid, they will thicken and solidify upon standing.
  • Check with your physician before starting any new supplement.
  1. Increase water intake while increasing fiber intake.
  • For fiber to function optimally, additional water is required.
  • Drink at least 8 8-ounce glasses of water per day when increasing fiber intake.
  • If not enough water is consumed when increasing fiber intake, there is a risk of becoming impacted where stool gets dry and hard and gets trapped in the rectum. It is not passable and must be surgically removed.

Here is a chart with some high fiber choices and their fiber content:

Food

Amount

Fiber Content (grams)

Fruits

 

 

Raspberries

1 cup

8.0

Blackberries

1 cup

8.0

Pear

1 medium

4.0

Apple with skin

1 medium

3.0

Strawberries

1 cup

4.0

Blueberries

1 cup

4.0

Banana

1 medium

3.0

Prunes

4 whole dried

6.0

Vegetables

 

 

Artichoke

1 cup cooked

14.0

White potato with skin

1 medium

5.0

Sweet potato with skin

1 medium

3.0

Spinach

½ cup cooked

3.0

Broccoli

½ cup cooked

2.0

Cauliflower

½ cup cooked

2.0

Carrots

½ cup cooked

2.0

Asparagus

5 medium

2.0

Tomato

1 medium

1.0

Grains, Beans, Nuts, and Seeds

 

 

Bran Cereal

1 cup

20.0

Black Beans

1 cup

14.0

Lentils

1 cup

13.0

Oats

1 cup cooked

4.0

Kidney Beans

1 cup

12.0

Flax Seeds

3 T.

7.0

Peanuts

½ cup

6.0

Brown Rice

½ cup cooked

2.0

Whole Wheat Bread

1 slice

2.0

Spaghetti Noodles

1 cup cooked

2.0

Peanuts

½ cup

6.0

Source:  National Fiber Council