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Estimates suggest that 40 per cent of chidren have levels of the vitamin below recommended thresholds, because of a combination of poor diets and lack of exposure to sunshine.

Currently, parents are advised that under-fives should have daily vitamin drops, but they are only given free to deprived families as part of Healthy Start programmes.

NICE will examine whether all children between six months and the age of five should receive the vitamins A, C and D via drops or tablets.

Prof Davies said: "We know that many children, not just in vulnerable groups have vitamin deficiencies. We are seeing again rickets.. it is appalling."

She said a scheme in Birmingham to offer free vitamin D supplements to all children has halved the number of cases of rickets and other vitamin D deficiency problems in the area.

Between 1998 and 2011, the number of cases of rickets admitted to hospital each year increased more than five-fold, from 147 to 762, official figures show.

Doctors said the disease had returned because today's children spend far more time indoors on their computers than previous generations, instead of playing outside with friends, often eating poorer diets.

Messages to protect children from skin cancer meant some parents were smothering on too much sunscreen, so that their offspring did not absorb enough vitamin D.

Dr Sarah Jarvis, a GP in inner city London, said she has seen increasing cases in recent years: "Children just don't spend as much time outside as they did in the past, and parents who have taken note of messages to protect children against skin cancer are sometimes too extreme with the sunscreen, so that children don't get any exposure."

Doctors said children were less likely to be given cod liver oil, a good source of vitamin D, which was often given to previous generations, and sometimes rejected the types of food such as oily fish which contain it.

The best source of vitamin D, which is essential for keeping bones and teeth healthy, is sun on the skin but it also occurs in some foods, such as oily fish and eggs, and is added to some items such as fat spreads and breakfast cereals.

Vitamin A, found in dairy, fortified fat spreads, carrots, sweet potatoes, swede, mangoes and dark green vegetables such as spinach, cabbage and broccoli is essential for strengthening the immune system, vision and maintaining healthy skin. Vitamin C, which boosts the immune system and helps the body absorb iron can be found in many fruits and some vegetables.

Dr Tim Cheetham, a consultant paediatrician at Royal Victoria Infirmary in Newcastle, said: "There are a combination of reasons - diet and also ethnic background play a part, because dark skin absorbs less vitamin D, but certainly reduced exposure to sunlight is one of the reasons why we are seeing increasing cases."