Monday 19 July 2010

Eating healthy fruit and vegetables won't stop cancer

Eating healthy fruit and vegetables won't stop cancer

* By Clair Weaver
* From: The Sunday Telegraph
* August 26, 2007 12:00AM

FRUIT and vegetables provide no protection against cancer, according to latest Australian research that has shocked nutritionists.

In a discovery that turns conventional advice on its head, experts have admitted there is "zero evidence" that eating fruit and vegetables can help people avoid a disease that kills nearly 40,000 Australians every year.


Research presented for the first time at last week's CSIRO Prospects for Cancer Prevention Symposium shows that what people eat is far less important in cancer prevention than previously believed.


Instead, the three prime risk factors driving up Australian cancer rates have been identified as obesity, drinking too much alcohol and smoking.


Staying within a healthy body weight range was found to be more important than following particular nutritional guidelines.

This means a slim person who doesn't eat enough fruit and vegetables would probably have a lower risk of developing cancer than someone who is overweight but eats the recommended daily amount of fruit and vegetables.


The findings emerged from the Cancer Council's Melbourne Collaborative Cohort Study, an ongoing research project involving 42,000 Australians who have been monitored since 1990.


Revealed exclusively to The Sunday Telegraph, they challenge widespread belief in the power of juices and vegetable-based "anti-cancer" diets to avoid or fight various types of the disease.

Dr Peter Clifton, director of the CSIRO's Nutrition Clinic, told The Sunday Telegraph there was "zero evidence" that eating fruit and vegetables could protect against cancer.


Heart disease is Australia's biggest killer, so fruit and vegetables are still regarded as important in maintaining health.


Professor Dallas English, of the Cancer Council of Victoria, told the symposium that despite decades of research, there was no convincing evidence on how Australians could modify their diet to reduce the risk of cancer.


"The most important thing about diet is limiting energy (kilojoule) intake so people don't become overweight or obese, because this has emerged as a risk factor for a number of cancers, including breast, prostate, bowel and endometrial (uterus)," he said.


The link between eating red meat and bowel cancer was "weak" and the Cancer Council supported guidelines advising people to eat red meat three or four times a week, Professor English said.


His advice comes after Health Minister Tony Abbott last week backed a report, funded by Meat & Livestock Australia, on the dietary role of red meat.


Surprisingly, fibre was deemed to have no significant benefit in avoiding bowel cancer _ although calcium was associated with a 20 per cent reduced risk.


Likewise, a high intake of fat, considered a prime culprit since the 1970s, was found to have only a "modest" link to breast cancer.


Smoking caused one in five cancer deaths, while regularly drinking too much alcohol boosted the risk of several cancers including breast and bowel, Professor English said.


He and Dr Clifton acknowledged that eating fruit and vegetables might help people avoid obesity, as they were lower in kilojoules than other foods.


"The risk of every type of cancer is increased by obesity," Dr Clifton added.


Both experts predict a surge in cancer as a result of Australia's obesity epidemic, but say exercise can play a vital role in cutting cancer rates, potentially halving the risk of some cancers.


Sydney mother Tauri Smart, 29, said the findings "take the pressure off" meal preparation.


She and her husband try to eat healthily and want to set a good example for their daughters Poppy, 3, and Sadie, six weeks.


"I've always tried to push fruit and vegetables, and have a vegetarian meal at least once a week," Ms Smart said. "Being able to have meat makes it easier."


Nutritionist Dr Rosemary Stanton cast doubt on the findings and suggested the study could be flawed.