For many years, the nutrition message has been "five a day" – the recommendation that five portions of fruit and vegetables are enough to keep disease at bay and help us to live longer. That advice has been revised upwards. A new study suggests that people who get seven or more portions a day are healthier. Researchers from University College London studied the dietary habits of 65,000 adults over a seven-year period. They concluded that: "A robust inverse association exists between fruit and vegetable consumption and mortality, with benefits seen in up to 7-plus portions daily." In other words, if you eat more fruit and vegetables, chances are you live longer.

The researchers put people into five different groups, depending on how much fruit and veg they ate. They found that those who ate seven or more portions a day had a 42 per cent lower risk of death than those who ate just one portion. They recommended that schools serve healthier meals and that supermarkets put more emphasis on prominently displaying cheaper produce. They warned that frozen and canned fruit was linked to higher mortality rates. Some experts say the findings of the study should be taken with a pinch of salt. One dietician said the findings ignored the fact that people who eat more fruit and veg are generally wealthier and thus lead lifestyles that will help them live longer anyway.