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Fiber up to fight cancer
Can I take a supplement instead?

How much fiber do I need?
How much fiber do I need?

The National Academy of Sciences’ Institute of Medicine recommends:

 MenWomenAges 50 and younger38 grams25 gramsAges 51 and older*30 grams21 grams

Elderly people may need slightly less and should check with their doctors for the appropriate amount of fiber to eat.


How can I get ENOUGH?
How can I get ENOUGH?

Eating more high-fiber fruits, vegetables, whole grains, nuts and legumes at meals and snack times can help you meet your daily fiber quota. Consider these easy substitutions:

Instead of thisHave thisFor this much fiber1 cup corn flakes3/4 cup bran flakes5 grams1 cup white rice1 cup brown rice2.5 gramscroutons on your salad1/2 cup beans on salad4.5 grams2 graham cracker squares1 ounce mixed nuts2.6 grams1 banana1 cup fresh raspberries5.6 grams

Did you know that adding fiber to your diet is one of the easiest steps you can take to fight disease, including some cancers? A fiber-rich diet tends to be lower in calories, take up more space on your plate and fill you up better than a low-fiber diet, helping you maintain a healthy weight, which will reduce your cancer risk. Many cancers are associated with being overweight, such as cancers of the stomach (in men), liver, pancreas, prostate, cervix, ovary, breast (in postmenopausal women) and uterus. Obese women, for example, have double the risk of developing breast cancer and dying from the disease than do women who maintain a healthy weight.

Some scientists say a high-fiber diet lowers your risk for colorectal cancer. In fact, a National Cancer Institute study of 34,000 people found that those who ate the most fiber were 27 percent less likely to develop colon polyps than those who ate the least. And a European study of a half-million people determined that those who eat little fiber could reduce their colon cancer risk by 40 percent by doubling their fiber intake. These researchers speculate that fiber binds potential carcinogens (cancer-causing substances) and helps water move them through the colon more rapidly, reducing the amount of time your colon is exposed to them.

It’s time to think about adding more fiber to your diet. Check out the charts below to find out how much fiber you need and how to get it.

Can I take a supplement instead?

Long-term use of fiber supplements doesn’t appear to be harmful and may help people who have conditions like irritable bowel syndrome and for whom dietary changes aren’t adequate. Timing is important, though. Taking a fiber supplement with your multivitamin could prevent your body from absorbing certain nutrients, so follow label instructions.

What’s more, getting fiber out of a bottle means you miss out on food’s disease-fighting vitamins, minerals and plant chemicals, such as the anti-oxidants lycopene in tomatoes and beta-carotene in pumpkin. Some scientists think these nutrients may work with fiber to lower cancer risk.

And don’t pass up lower-fiber options you know are healthy. For example, a half cup of strawberries contains only one gram of fiber. But strawberries contain vitamin C and other disease-fighting nutrients. Cover your nutritional bases by eating a variety of fruits and vegetables.

Adding more dietary fiber to an otherwise unhealthy lifestyle won’t protect you against cancer—but it could be an important first step toward making further lifestyle improvements that, taken together, reduce your cancer risk.