Dieting can help fight cancer: Medical myth?

Leslie Michelson does not have prostate cancer, but as chief executive officer of the Prostate Cancer Foundation he knows all too well how bad the disease is. So Michelson, 54, changed his diet. He used to avoid cruciferous vegetables, like cauliflower and brussels sprouts, hating their taste.
Now he has them three or four times a week. He rarely ate fish, but now has it three times a week.He eats tomato sauce at least twice a week. "I'm persuaded that with prostate cancer, diet makes a difference," he said. Michelson is one of a growing number of people worried about cancer who are turning to diets for protection.
Cancer patients, doctors say, almost always ask what to eat to reduce their chances of dying from the disease. The diet messages are everywhere:
The National Cancer Institute has an 'Eat 5 to 9 a Day for Better Health' programme, the numbers referring to servings of fruits and vegetables, and the Prostate Cancer Foundation has a detailed anticancer diet. Yet despite the often adamant advice, scientists say they really do not know whether dietary changes will make a difference.
And there lies a quandary for today's medicine. It is turning out to be much more difficult than anyone expected to discover if diet affects cancer risk. Hypotheses abound, but convincing evidence remains elusive. Most of the proposed dietary changes are unlikely to be harmful ��� less meat, more fish, more fruits and vegetables and less fat.
And these changes in diet may help protect against heart disease, even if they have no effect on cancer. So should people who are worried about cancer be told to follow these guidelines anyway, because they may work and will probably not hurt?
Or should the people be told that the evidence just is not there, so they should not deceive themselves? Dr Barnett Kramer, deputy director in the office of disease prevention at the National Institutes of Health, said:
"Over time, the messages on diet and cancer have been ratcheted up until they are almost co-equal with the smoking messages. I think a lot of the public is completely unaware that the strength of the message is not matched by the strength of the evidence."
NYT News Service