CHANGING lifestyles among children is leading to a Vitamin D deficiency and a rise in cases of rickets, North-East medical experts said today.

They said youngsters were spending more time indoors on their computers rather than previous generations who spent time playing outside with their friends.

Two medical experts have called for Vitamin D to be added to milk and other food products.

They said modern diets often lack Vitamin D and this could be a big reason - along with changing lifestyles - for the increasing health problems, in particular rickets in children.

Writing a clinical review in the latest issue of the British Medical Journal, Professor Simon Pearce and Dr Tim Cheetham, of Newcastle University, call for a change in public health policy.

Prof Pearce, a professor of endocrinology, said: "Kids tend to stay indoors more these days and play on their computers instead of enjoying the fresh air.

"This means their Vitamin D levels are worse than in previous years.

"A change in public health policy is required. Health professionals have been slow to deal with this problem, even though we have known about it for a while.

"Some measures have been taken, but the number of patients still presenting with symptoms of Vitamin D deficiency shows we have a long way to go."

Rickets, where children develop painful and deformed bow-legs and do not grow properly, is a condition linked with poverty, starvation, Victorian times or those in the developing world - not with 21st century Britain.

But it is a very real concern, with several studies showing that numbers are increasing. More than 20 new cases are discovered every year in Newcastle alone.

Dr Cheetham, a senior lecturer in paediatric endocrinology, said: "I am dismayed by the increasing numbers of children we are treating with this entirely preventable condition.

"Fifty years ago, many children would have been given regular doses of cod liver oil, but this practice has all but died out."

Half of all adults in the UK have Vitamin D deficiency in the winter and spring, and one in six having severe deficiency.

This is worse in the north of England and could be part of the reason for the health gap between the north and south, the experts said.

And the condition has been linked to cardiovascular disease, type 2 diabetes, several cancers, and autoimmune conditions as well as osteomalacia, which is the painful manifestation of soft bones in adults.

The main source of Vitamin D is sunlight, through skin exposure. But it is also present in a small number of foods, such as oily fish or cod liver oil.

There are several high risk groups who are most in danger from suffering from deficiency including people with skin pigmentation, those who use sunscreen or concealing clothing, being elderly or institutionalised, people who are obese, and those suffering from renal and liver disease.

Prof Pearce added: "We believe that a more robust approach to statutory food supplementation with Vitamin D, for example in milk, is needed in the UK, as this measure has already been introduced successfully in many other countries in similar parts of the world."