Fruit and veg: Five-a-day is okay, says study
How many portions of fresh fruit and vegetables do we need a day to be healthy?
British nutritionists said in April that the magic number was seven.
That was two more portions that famous five-a-day recommendation made by the UN’s World Health Organisation (WHO) in 2003.
Who's right? Who's wrong? A new foray into the arena of sound eating suggests that five is just right.
Reduced risk of premature death
Researchers in China and the United States trawled through 16 published investigations into diet and health involving more than 830,000 participants, who were followed for periods ranging from four and a half years to 26 years.
Every additional daily serving of fruit and vegetables reduced the average risk of premature death from all causes by five per cent, the scientists found.
Over the period of the studies, 56,000 of the participants died, researchers said. In the case of death from a heart attack or a stroke, each additional serving curbed risk by four per cent.
But there was no evidence of an additional fall in risk beyond five portions, according to the review, published online on Tuesday by the British Medical Journal (BMJ).
“We found a threshold of around five servings a day of fruit and vegetables, after which the risk of death did not reduce further,” said the investigators, led by Mr Frank Hu of the Harvard School of Public Health in Boston, Massachusetts.
Still at risk for death from cancer
High consumption of fruit and vegetables did not translate into a significant reduction in the risk of death from cancer, the study also found.
In addition to advising patients about the virtues of healthy eating, doctors should also push home the message about risks from obesity, inactivity, smoking and excessive drinking, said the paper.
In April, researchers at University College London found that eating seven daily portions or more could reduce the risk of cancer by 25 per cent and of heart disease by 31 per cent, compared to people who consumed less than one portion a day.
The study was based on the eating habits of more than 65,000 people in England between 2001 and 2008.
The WHO guidelines are based on the equivalent of five 80g portions. One portion is roughly equivalent to a medium-sized apple, a bowl of mixed salad or three dessert spoonfuls of raw, cooked, canned or frozen vegetables.