The large trial on nearly 30,000 women of post-menopausal age found that women who followed only one or none of the nine recommended diet and lifestyle guidelines, developed by the American Institute for Cancer Research (AICR), had a 35 per cent higher risk of developing cancer than women who practiced at least six of the recommendations.
Dr James Cerhan, head of Mayo Clinic Cancer Center's genetic epidemiology and risk assessment programme and leader of the research study, commented that women who followed only one or none of the recommendations had a 42 per cent higher risk of dying from cancer.
"Furthermore, we estimate that if all the women in the study group had never smoked and followed a majority of the guidelines, approximately 30 per cent of new cancers and cancer deaths could have been prevented or delayed in the study group," he said.
It is believed, say the researchers, to be the first study to show the actual impact of following the AICR recommendations, which include not smoking, controlling body weight, exercising regularly and eating a balanced diet.
"Our findings indicate that even at an older age, women who choose to eat and live healthier can reduce their risk of developing or dying from cancer," Dr Cerhan added. "We think this is very positive, empowering news."
Food manufacturers are increasingly turning to health-boosting ingredients in their food formulations to cash in on the growing desire by consumers to ease health concerns through diet. According to a recent Datamonitor report, 'Changing needs in functional food and drinks', the rapidly growing functional foods industry has seen its consumer base expand beyond consumers with specific medical needs to include those who are merely concerned about future health risks and even those who find that functional foods offer lifestyle benefits.
"Functional foods are filling an increasingly important part of our lifestyle, as we look to products enhanced with particular ingredients to get us through the day. There is an increasing demand from consumers who have no medical concerns, but who find that their lifestyle is improved or enhanced by the inclusion of gut health products in their diet, for example," said Andrew Russell, author of the report.
More than 10 million people are diagnosed with cancer every year, according to World Health Organisation (WHO) figures, causing 6 million deaths every year or 12 per cent of deaths worldwide.
"We now know enough about the causes of cancer to prevent at least one-third of all cancers. Cancer is largely preventable: by stopping smoking, providing healthy food and avoiding the exposure to carcinogens," writes the UN-backed organisation.
The study at the Mayo Clinic examined self-reported information from 29,564 Iowa women about their diet and lifestyle habits. The information was gathered in 1986 and the women were between 55 and 69 years of age. The women were then followed for 13 years to determine what effect the recommended diet and lifestyle practices had on reducing the risk of them getting cancer and dying from it.
The nine diet and lifestyle recommendations studied included: not smoking, regular exercise, eating five or more servings of vegetables and fruits each day, limiting alcoholic drinks to one drink a day for women and limiting intake of fatty foods, particularly those of animal origin, and controlling intake of salted foods and use of salt in cooking.
"We think that it is highly plausible that our findings could be replicated in a broader population, including men and young adults, and be an effective and cost-efficient way to reduce the impact of cancer on individuals and on our communities," said Dr Cerhan.