Eating more fruit and vegetables has only a modest effect on protecting against cancer, a study into the link between diet and disease has found.
The study of 500,000 Europeans joins a growing body of evidence undermining the high hopes that pushing “five-a-day” might slash Western cancer rates, with the international team of researchers estimating that only around 2.5% of cancers could be averted by increasing intake.
In 1990, the World Health Organization recommended that everyone consume at least five portions of fruit and vegetables a day to prevent cancer and other chronic diseases.
The advice has formed a central plank of public health campaigns in many developed countries. It has been promoted in the UK since 2003 and in the US for nearly two decades.
But research has failed to substantiate the suggestion that as many as 50% of cancers could be prevented by boosting the public’s consumption of fruit and vegetables.
The team, led by researchers from the Mount Sinai School of Medicine, in New York, took into account lifestyle factors such as smoking and exercise when drawing their conclusions.
But writing in the Journal of the National Cancer Institute, they said they could not rule out that even the small reduction in cancer risk seen was down to the fact that the kind of people who ate more fruit and vegetables lived healthier lives in many other respects too.
But experts stress eating fruit and vegetables is still key to good health. Yinka Ebo of Cancer Research UK said: “It’s still a good idea to eat your five-a-day but remember that fruits and vegetables are pieces in a much larger lifestyle jigsaw.