DENVER (AP) — New research raises the possibility that beta carotene pills could help ward off prostate cancer among men who skimp on fruits and vegetables.
The findings, part of a big study of physicians, found that those who get relatively little beta carotene in their food seem to reduce their prostate cancer risk by about one-third if they take the nutrient in pill form.
However, experts caution that the findings — released at a scientific conference in Denver on Monday — are still preliminary, and they are not ready to recommend these vitamin pills, even for those who won’t touch carrots.
The use of nutritonal supplements, especially beta carotene, is controversial. The latest findings underscore just how complicated the relationship between dietary nutrients and health is turning out to be.
Many studies have shown that people who eat plenty of fruits and vegetables are less likely to get all kinds of cancer, including prostate cancer, the second-leading cancer killer of American men after lung cancer.
Beta carotene, a form of vitamin A, is one of many nutrients found in fruits and vegetables. Since it seemed reasonable that pills containing vegetable nutrients would be good for people, several big studies of beta carotene and other supplements were launched in the 1980s. But as the results have come in, it appears these pills are no substitute for good eating.
“You probably really have to eat your carrots and not just take supplements,” said Dr. Alfred I. Neugut of Columbia University.
The first hint that beta carotene pills might not be as beneficial as many had hoped came three years ago from a 10-year study of smokers in Finland.
Researchers expected that giving these men beta carotene supplements would reduce their risk of lung cancer. But to their surprise, they found that those getting the pills actually had 18 percent more lung cancer.
Last year, more results came in from the Physicians Health Study, which randomly assigned 22,071 American doctors to take beta carotene or dummy pills beginning in 1982. The pills had no effect at all — good or bad — on overall cancer risk.
Questions remained, however, about whether they might do some good for those who get relatively little beta carotene in their diets.
On Monday, Dr. Meir Stampfer of Brigham and Women’s Hospital in Boston presented more data from the physicians study suggesting that the supplements might indeed help protect such people from prostate cancer.
In a presentation at a meeting of the American Society of Clinical Oncology, he showed that those whose blood levels of beta carotene were low at the study’s start reduced their risk of prostate cancer over a 12-year period by 36 percent if they took beta carotene.
Stampfer said the study will continue for several more years to examine the question.