A hospital has revealed that more than 20% of children from across the social spectrum have shown signs of rickets.
Doctors who uncovered the bone disease problem were left astonished by their discovery - which they said was reminiscent of 17th-century England.
The findings came after consultant orthopaedic surgeon Professor Nicholas Clarke checked more than 200 children from Southampton for bone problems caused by a lack of vitamin D.
The trend, which has seen many children eating poor diets lacking in nutrition, has led to a rise in the disease across the country.
Children spending too much time indoors was also said to be behind the rise.
Normally, the body takes in vitamin D in the form of sun-synthesis through the skin, but eggs and oily fish such as mackerel also contain the vitamin.
Those deficient in the vitamin can suffer weak and bowed bones.
"A lot of the children we've seen have got low vitamin D and require treatment," the doctor said.
"In my 22 years at Southampton General Hospital, this is a completely new occurrence in the south that has evolved over the last 12 to 24 months and we are seeing cases across the board, from areas of deprivation up to the middle classes, so there is a real need to get national attention focused on the dangers this presents.
"The return of rickets in northern parts of the UK came as a surprise despite the colder climate and lower levels of sunshine in the north, but what has developed in Southampton is quite astonishing."
Rickets is traditionally a poverty-linked bone disease that generally disappeared around 90 years ago following the discovery in the 1920s of vitamin D. It was endemic in poor Victorian England.
Professor Clarke said vitamin D supplements should be more widely adopted to halt the rise in cases.