Healthy Diet May Not Vanquish Breast Cancer

Contrary to past research, a healthy diet may not prevent breast cancer.

ByABC News
July 17, 2007, 8:15 PM

July 17, 2007— -- There are many things a breast cancer survivor can do to keep her cancer at bay -- but eating a diet that is high in fruits and vegetables isn't one of them, new research suggests.

But cancer experts not affiliated with the study were quick to react to the findings, fearing that the new research would discourage breast cancer survivors from pursuing a healthy diet -- a dangerous move, in their opinion.

In the study, released Tuesday in the Journal of the American Medical Association, researchers at the University of California, San Diego enrolled more than 3,000 breast cancer survivors.

Half the women studied ate five or more servings of fruits and vegetables per day, as is recommended by the U.S. Food and Drug Administration. The other group of women ate five servings of vegetables plus three servings of fruit, along with 30 grams of fiber every day. They also reduced their fat intake to 15 to 20 percent of their daily caloric intake; Americans generally get 30 to 40 percent of their calories from fat.

After seven years, the women who reported eating a superhealthy diet appeared to be no more likely to be cancer-free than the women who ate just the healthy diet.

Even the researchers were somewhat surprised by what they found.

"What really surprised us was the absolute lack of difference between the groups," says lead study author John Pierce of the Cancer Prevention and Control Program at UCSD.

"The lines [of cancer recurrence] were just literally on top of one another, and we were not expecting that."

The study's results seem to directly contradict a study last year that showed that breast cancer survivors who ate a low-fat diet reduced their risk of a repeat cancer diagnosis.

There are a number of reasons why the study may have found what it did. For one, the women were self-reporting their eating habits -- possibly leading to dubious results.

"People ate less toward the end [of the study]," says Keith Ayoob, associate professor of pediatrics at Albert Einstein College of Medicine. "But they either didn't lose weight or actually gained weight. This puts a bit of strain on the credibility of the self-reporting."