The Economist

Eating lots of fruit and vegetables may not help stave off cancer, after all
The Economist

For snivelling children and recalcitrant carnivores, requests that they should eat five portions of fruit and vegetables every day have mostly fallen on deaf ears. But those who did comply with official advice from charities, governments and even the mighty World Health Organisation (WHO), could remind themselves, rather smugly, that the extra greens they forced down at lunchtime would greatly reduce their chances of getting cancer. Until now, that is. Because a group of researchers led by Paolo Boffetta, of the Mount Sinai School of Medicine in New York, have conducted a new study into the link between cancer and the consumption of fruit and vegetables, and found it to be far weaker than anyone had thought.

In the past, veggie-associated reductions of cancer-risk rates as high as 50% had been reported. But it appears that some of these early investigations may have been biased by the use of “case-control” studies.

Dr Boffetta and his colleagues have therefore carried out a different kind of study, known as prospective cohort study, which they report in the Journal of the National Cancer Institute. Their work follows a group of individuals over time and looks at how different factors contribute to different outcomes—in this case, the development of cancer. Analysis of dietary data from almost 500,000 people in Europe found only a weak association between high fruit and vegetable intake and reduced overall cancer risk.