Diet found to not help breast cancer survival

Despite high hopes, a diet loaded with fruits and vegetables doesn’t seem to help women survive breast cancer, researchers reported Tuesday.

But experts said that doesn’t mean a diet of cheeseburgers and beer is the way to go. Even though scientists haven’t proved it, “there’s a lot of evidence from observational studies that maintaining a healthy weight and moderate or no alcohol consumption are associated with lower risk” of breast cancer, said Susan Gapstur, associate director of cancer prevention at Northwestern University.

One possible reason for the high-veggie diet’s apparent lack of benefit, the researchers said, is that the women in the study did not lose weight or increase their physical activity.

The study, published in this week’s Journal of the American Medical Assn., involved more than 3,000 women who had been treated for early breast cancer. Half were asked to follow the government’s recommendations for eating five servings of fruit and vegetables a day.

The rest were regularly counseled to consume five daily servings of vegetables, three servings of fruit and 16 ounces of vegetable juice. This group also was told to eat 30 grams of fiber a day (the equivalent of 10 apples) and to get only 15% to 20% of their calories from fat.

For a woman consuming 1,500 calories a day, that meant no more fat than that in a McDonald’s Quarter Pounder and a small order of French fries.

The women, ages 18 to 70, were enrolled in the study between 1995 and 2000 and followed until 2006. In that time, 518 women had recurrences of their breast cancer, and 262 died of the disease. But they were evenly divided between the diet group and the control group.

The study, conducted by John Pierce and colleagues at UC San Diego, appeared to contradict the findings of a trial reported last year, in which breast cancer survivors who reduced their fat intake were found to be less likely to suffer a relapse.

However, food diaries kept by the participants in the new study showed they never reached the goal of getting fewer than 20% of their calories from fat. They consumed more fruit, more vegetables, more fiber and less fat than the comparison group, but after an average seven years of follow-up, average fat intake was 29%, or slightly higher than it was when they started. The control group was at 32%.

Gapstur, who was not involved in the study but wrote an editorial accompanying the JAMA report, said the results showed how hard it was to get research participants to adhere to specific behavioral goals.

According to the National Cancer Institute, which sponsored the study, very few things are proven to prevent breast cancer or reduce the risk of its recurrence. They include drugs that block the action of the hormone estrogen on breast cells, such as tamoxifen, as well as surgical removal of the ovaries, which produce estrogen. There is also some evidence that exercise reduces risk, especially in younger, thinner women.

Women can also avoid certain risk factors that increase their chances of getting breast cancer, researchers said. Those include X-rays, especially in younger women; obesity; hormone therapy, and probably alcohol.