Cranberries help you see in the dark

Delia Smith will be delighted: cranberries have been found to contain essential chemicals that improve night sight. Meanwhile broccoli, tomato skins and even green tea all turn out to have health benefits that a few decades ago were thought not to exist.

Delia Smith will be delighted: cranberries have been found to contain essential chemicals that improve night sight. Meanwhile broccoli, tomato skins and even green tea all turn out to have health benefits that a few decades ago were thought not to exist.

"Selenium used to be thought of as a highly toxic substance - it was only in the 1970s that some people began to realise the essential role it plays in human nutrition," Peter Berry Ottaway, a consultant in food science, told the British Association yesterday.

"The 20th century has only been the beginning in understanding how nutrition works."

He forecast that "in the near future" processed foods would have traces of essential nutrients added to them because families today "find it impossible to eat the daily recommendation of five portions of fruit and vegetables".

Fruits such as cranberries, blackberries, bilberries and the skins of black grapes contain chemicals called anthocyanins, which help the eye adapt to the dark. Similarly lutein, found in green vegetables, has now been found to lower the risk of age-related macular degeneration which causes blindness; while tomatoes contain the red pigment lycopene, which has been found to blot out "free radicals" of highly reactive oxygen atoms in the body, which could otherwise damage cells and perhaps even lead to cancer.