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Eat Fiber, Fight Cancer

Focused on Health - March 2012

by Colleen Martin

woman eating appleWhen you think fiber, what comes to mind? Your favorite breakfast bar or a sugar substitute with added fiber?

Think again! The best source of this important nutrient is natural plant-based foods.

According to the American Institute for Cancer Research (AICR), plant-based foods rich in dietary fiber may reduce your risk for colorectal cancer. That’s because the more fiber you consume, the less time harmful toxins spend inside your body.

“The phytochemicals in dietary fiber help protect our cells from becoming damaged, which can lead to cancer,” says Clare McKindley, clinical dietitian at MD Anderson’s Cancer Prevention Center.  “Plus, a high-fiber diet may help reduce your overall calorie intake and help you maintain a healthy weight, which is vital to reducing cancer risk.”

And, that’s not all. The National Institutes of Health's AARP Diet and Health Study found that people who eat a high-fiber diet may live longer than people who skimp on the fiber. Other benefits of a diet high in dietary fiber include:

  • Feeling full longer. Dietary fiber includes a form of carbohydrate that people can’t digest. The fiber slows the speed at which food and drink leave your stomach. So, you stay full longer after each meal or snack.
  • Weight control. Many high-fiber foods are low-calorie and packed with disease-fighting nutrients. That’s good news since maintaining a healthy weight throughout life is one of the most important factors in preventing cancer and other diseases.
  • Lower cholesterol. Some fibers help prevent fat and cholesterol absorption, helping you lower your cholesterol over time.
  • Lower blood sugar levels. Diabetic? Or at risk of becoming diabetic? Fiber can positively influence blood sugar levels by managing how quickly sugar gets into your blood stream.
  • Bowel management. Have digestive problems? Adding fiber to your diet can help protect your intestinal lining and make bowel movements easier or more frequent.

dinner plateFill two-thirds of your plate with plant-based fiber sources

To reap the benefits of fiber, though, women need to consume at least 25 grams a day and men need to consume 38 grams a day, according to the Dietary Guidelines for Americans

Not sure you can pack that much fiber into your diet? Aim for these portion sizes at meal times:

  • Two-thirds of your plate should be filled with fiber-rich/non-starchy vegetables (like broccoli and dark, leafy greens) fruits, beans and whole grains.
  • One-third (or less) of your meal should be your poultry or fish. Limit red meat (beef and pork) to less than 18 ounces per week. A recommended serving of red meat is 3 ounces, which is the size of a deck of cards.

glass of waterTake it slow

Increase your fiber intake gradually. Adding large amounts of fiber to your diet too quickly can cause a stomachache, discomfort or gas.

Beans, peas, broccoli, cabbage, onions, asparagus, natural milk sugar, apples, prunes, pasta and corn are some of the biggest offenders. So, add these fibers gradually to improve your body’s tolerance.

Make sure to stay hydrated by drinking plenty of water, and contact your doctor if you’re having trouble digesting high-fiber foods.

It’s okay to supplement your diet with man-made fiber sources like fiber bars and cereal. But remember, you should get most of your fiber from plant-based foods. Not only will you reap the benefits of fiber; you’ll boost your overall health with all the vitamins, minerals, phytochemicals and antioxidants these foods provide.

Related Links
Rough Up Your Diet (National Institutes of Health)
The Facts About Fiber (AICR)
Five Colorful Foods, One Magical Rainbow (MD Anderson)
Fiber: How Much Is Enough? (MD Anderson)

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© 2014 The University of Texas MD Anderson Cancer Center