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Nutrition in a Nutshell #3: Why Fiber?
by Barbara Hiebert, R.D.

Many of us know that fiber is supposed to be a "good thing," but just how good is it? That answer depends on what type of fiber and how much fiber a person consumes. Basically, there are two types of fiber: soluble and insoluble. Both are beneficial.

Insoluble fiber is commonly referred to as "roughage" and is found in whole grains, wheat bran and vegetable skins. It provides exercise for the intestine, preventing hemorrhoids, constipation, and other bowel problems. Insoluble fiber also reduces the risk of colon cancer.

Soluble fiber is found in peas and beans (legumes of any kind), oats, barley, apples, oranges, bananas, other fruits and carrots. This type of fiber helps to lower blood sugar and may lower blood cholesterol levels.

How much fiber should we eat? The National Cancer Institute and the American Dietetic Association recommend 20-35 gms. per day. Check the fiber foods listed below to estimate your intake (content listed in grams):

Fruits: Vegetables ( c.) Breads/Grains
pear 4.3 bkd. potato w/skin 3.6 bran Muffin 2.8
strawberries 4 /cup corn 3.4 rye crackers 2.2/ 2
orange 3.1 brussels sprouts 3.4 whole wheat 1.9/slice
apple 2.3 sweet potato 3.4 pumpernickel 1.9/slice

Beans ( cup): Cereals ( 1/3 cup):
black-eyed peas 8.5 wheat bran 11.4
black beans 7.7 all-bran 8.5
kidney beans 7.3 bran chex 2.3
baked beans 7.0 raisin bran 1.8

Need to add more fiber to your diet? Here are some tips:
- Add fiber gradually, over several weeks to allow your body time to adjust.
- Drink more fluids (at least 8 cups or glasses per day).
- Sprinkle wheat bran on your breakfast cereal.
- Spend a little extra to buy the pre-prepared "baby carrots" you can eat out of the bag.
- Use whole wheat flour in place of all or part of the white flour in recipes. Increase liquid by 1-2 Tbsps. per cup of flour substituted.
- Read product labels in the grocery store to compare fiber content.
- Eat fresh fruit and cooked vegetables with skins.
- For families with small children: buy a "healthy cereal" to serve, but allow the children to sprinkle on a "sugar cereal" as a decoration.

For more information, contact me at: bhiebert@jhmi.edu.