MILLIONS of Britons are deficient in a vitamin that protects against diseases including rickets, diabetes and cancer, it was said yesterday.

Experts called for urgent action to raise vitamin D levels, particularly among breast-feeding women, young children, and people with dark skin.

They suggested one remedy might be widening vitamin D fortification of food, possibly to include bread and milk.

At present, only breakfast cereals and margarines are fortified with vitamin D.

The experts also recommended taking vitamin D supplements such as cod liver oil.

Fear of the sun and an "indoor" culture were both said to have contributed to vitamin D deficiency in Britain and other western countries.

Dr Birgit Teucher, from the Institute of Food Research, said: ''Since the 1980s, it has become increasingly apparent that vitamin D has important roles."