Dr. Tim Says....

How to Eat Healthy:
Fiber Might Be the Best of All

[This is another in our series on the How and Why of Eating Healthy.]

Fiber is what your grandma used to call "roughage." It's not one particular food, but it's simply the part of foods that your body can't digest. Fibers are technically carbohydrates, but your body doesn't have the enzymes to break them down like it does with sucrose. As a result, they're not absorbed and essentially have no calories.

Fiber comes in two forms: soluble and insoluble.

Soluble fiber is thought of as "sticky" fiber and is more effective in lowering cholesterol. It is found in beans and some grains, such as oat bran, oatmeal and rye. Almost all fruits, such as apples, grapes, peaches, oranges and pears are high in soluble fiber (think sticky fruits). Most vegetables are also high in soluble fiber. Insoluble fiber is found in whole grain products like whole wheat flour, whole grain breads and pastas as well as cereal grains like rice, wild rice and seeds.

Most of us need to increase the amount of fiber in our diet. The average American gets only 10 to 15 grams of fiber per day, while 25 to 30 grams per day is optimum. There are simple ways to make changes that will put more fiber in your life.

For breakfast, choose whole grain cereals like Shredded Wheat, bran flakes, 100% bran and oatmeal. Take a moment in the grocery store to look at the box and compare the amounts of fiber in these cereals with the one you are eating. Look carefully, because many cereals will have higher fiber but will sometimes contain a lot of sugar as well.

If you like toast for breakfast, choose breads with higher fiber. Most bread will have only about two grams per slice, but it's easy to find choices with up to 5 grams. Even if the label says "whole wheat," you may find that it doesn't have much fiber. Check the label. Use the same high fiber breads for your sandwiches at lunch.

Simply substituting ingredients in your favorite dinner recipes can help you get more fiber. Use whole wheat pastas, brown rice and wild rice. Replace potatoes with sweet potatoes or yams. Choose recipes that contain beans and other legumes like lentils and split peas.

Snacking on fruit is a great way to get more fiber. Fruits that are good high fiber choices are apples, strawberries and raisins.

So why should you care? Quite simply there is so much excellent research now to support eating a high fiber diet.

We know that fiber helps prevent cancer and lowers the risk of heart disease. High fiber diets have been shown to reduce cholesterol levels and help diabetics control their blood sugars. Every week there's another study showing how important getting more fiber in your diet is.

In one study, researchers looked at the relationship between eating whole grains, refined grains or cereal fiber and the risk factors for heart disease, high cholesterol, and diabetes. That those with the highest intake of these foods had a lower BMI, weight, and waist circumference. They also had better cholesterol scores and a normal score in a 2-hour insulin reaction test (a common test for diabetes and pre-diabetic conditions).

One of my favorite pieces of research (on any topic) showed that those who ate a high fiber breakfast were more satisfied through the morning, ate less lunch and had improved blood sugar levels later in the day.

Researchers in Spain looked at a large scale, five year study of nutrition. They found that for men, higher fiber intake meant a lower risk of weight gain: up to 48% lower for the highest intake of fiber. For women, those eating the most fiber had a decreased risk of weight gain of 19%. And it's never too late to put more fiber in your diet. One study in those over 65 showed that those who consumed the highest level of cereal fiber (as opposed to vegetable or fruit fiber) had a 21% lower risk of heart disease than those who ate the least cereal fiber.

This is the easiest change you can make in your diet.

Eat well, eat healthy, enjoy life!

Timothy S. Harlan, M.D.
Dr. Gourmet
August 24, 2009
Last updated: 08/24/09