It is not necessary to eat five servings of fruits and vegetables every day to keep healthy but just enough for the body to assimilate the necessary vitamins and minerals, a British dietician says.

Catherine Collins, chief dietician at St George's Hospital in Tooting, says the fruits and vegetables can be spread out across a week. One can eat a lot one day and not much the next, but over a week he or she will still get the right amount of nutrients.

"The whole idea that you must meet some vitamin and mineral targets every day of your life is a marketing myth," she said. Collins's advice flies in the face of Britain's Five A Day campaign which encourages people to eat five pieces of fruit and vegetables every day to be healthy.