The News About Dietary Fiber

By CBSNews.com staff CBSNews.com staff

January 21, 1999 / 9:52 AM EST / CBS

You've stocked your shelves with cereal and loaded up on fruit. It's all part of a healthy high-fiber diet. But is fiber everything it's cracked up to be? A study in this morning's New England Journal of Medicine has surprising news.

CBS This Morning Health Contributor Dr. Bernadine Healy says researchers wanted to know if a high-fiber diet can help prevent colon cancer in women. The study looked at 90,000 nurses, all women, for a period of 14 years, and monitored their diets through questionnaires. At the end of this long period, they found there was no difference in colon cancer rates between those who took a diet rich in fibers and those who didn't.

But Healy warns against giving up on dietary fiber. "This study does not tell us that," she notes. "This is looking at a narrow group of young women from about 45 to an average age of 60."

Healy says more study is needed because the average age at which women get colon cancer peaks at 73.

She adds that high fiber diets are beneficial for other reasons: "They decrease your chance of getting heart disease, help control diabetes, and decrease the causes of other cancers - of the head and the neck and the esophagus," she notes.

About 20 to 30 grams of fiber a day is recommended, not including supplements. Here are some high fiber foods:

Peas: a half a cup will give you 4 grams of fiber.
Avocado: a medium one will give you 12 grams of fiber.
Raspberries: one cup gives you 8 grams of fiber.
Apple: one large apple will give you 6 grams of fiber.

Cereals, pastas, beans, and wheat bran also are high in fiber.

There are other preventive measures that women can take. Aspirin taken regularly can decrease risk of colon cancer, as can estrogen supplements

A warning: Healy says if you have a lot of fiber in your diet, it decreases your absorption of calcium. Women should take 1,000 to 1,200 milligrams of calcium a day, since a lack of calcium also is a risk factor for colon cancer.

Healy advises women to get early screenings if they have a family history of colon cancer. If polyps, which can be detected by a colonoscopy, are found, they must be removed.

But finally, she says, an apple a day is still a sound habit.