England's chief medical officer, Dame Sally Davies, is concerned that young children and some adults are not getting enough vitamin D. According to the BBC, she is to contact medical professionals about government guidelines which recommend that some groups, including under-fives, may require daily vitamin D supplements.

Not receiving enough of the vitamin can lead to health problems including rickets, broken bones, muscle weakness and infections including TB. Research last year suggested that a quarter of Britain's toddlers did not have enough vitamin D in their bloodstreams.

As evidence goes, the survey in October by the Feeding For Life Foundation is imperfect. Its conclusion is arresting and prompted plenty of media coverage. But, as the Department of Health pointed out, there is no national data available on how much vitamin D children of this age have in their blood. The authors looked only at vitamin D obtained from dietary sources – such as oily fish, cereal and margarine – and not from exposure to sunlight. The foundation receives financial backing from the baby food firm Cow & Gate.

Davies said: "We know a significant proportion of people in the UK probably have inadequate levels of vitamin D in their blood. Our experts are clear – low levels of vitamin D can increase the risk of poor bone health, including rickets in young children." People at risk of having too little vitamin D, including mothers-to-be and under-fives, are already advised to take supplements, she said.

Professor Mitch Blair, consultant paediatrician at Northwick Park hospital in London and the officer for health promotion at the Royal College of Paediatrics and Child Health, said he had seen a resurgence of rickets in the last two to three years. "The main reason is that the public aren't aware of the importance of vitamin D any more," he said.

"My most recent one was two weeks ago: a 16-month-old Asian boy who had very bow legs and wasn't walking. Blood tests done by his GP had established the child had a vitamin D deficiency. We started him on intensive treatment, supplements in syrup form rather than tablets, given his age, which he'll take for three months. That will reverse his rickets eventually and in time, hopefully in months, he'll start to walk", Blair said.

The boy's Asian heritage is relevant. Those at greatest risk of vitamin D deficiency are people with dark skin and those who live in northern Britain. Scotland's notably high rate of multiple sclerosis, which is also linked to lack of vitamin D, has prompted medical experts to call for food sold there to be fortified with it. Scotland's lack of sunshine is deemed to be the culprit.

Public awareness has declined since schemes such as free cod liver oil and free vitamins given out at baby clincs ended, Blair said. Dr Benjamin Jacobs, a consultant paediatrician at the Royal National Orthopaedic hospital in London, said such programmes were stopped because they were deemed "unnecessary, possibly harmful". In retrospect, he said, "that was a major mistake".

The NHS tries to tackle the problem through its Healthy Start scheme, which gives mothers from poorer backgrounds vouchers to exchange for either fruit and vegetables or supplements. Ninety per cent of those eligible join the scheme, but only 5% end up collecting the tablets – although take-up is better for fruit and veg. Doctors such as Blair believe it is an overly complicated scheme, especially for those for whom English is not their first language, and that simplification is needed.

The guidelines say children and pregnant women should have 400 units a day of vitamin D, but that is far less than is recommended elsewhere. In America, experts have suggested 4,000 units.

The Department of Health has asked the independent scientific advisory committee to review the evidence on how much vitamin D different population groups need. The likelihood must be that this review will lead to an increase in the amount certain groups are told to get, new initiatives to raise awareness of the problem and – the hard bit – ideas on how to get more of us to get more vitamin D.