Vitamin D supplements for Asian kids, say researchers

"We suggest that supplementation with vitamin D of all babies of Asian origin for the first 2 years of life might be the economic answer to a growing problem,"​ wrote lead author Christos Zipitis from Burnley General Hospital.

Such conclusions are based on a prospective study, which identified 14 children with vitamin D deficiency in the Burnley Health Care NHS Trust in the north west of England between 2000 and 2005.

Virtually all those affected were of Asian ethnicity, and none had received vitamin D supplements. The researchers extrapolated their results to show that the overall vitamin D deficiency in the general Trust population was 1 in 923, while children of Asian origin had an incidence of 1 in 177.

Many of the cases were identified by accident, when children came in for eczema, throat infections, diarrhoea and so one, which suggests that "there are many more patients with clinically silent vitamin D deficiency,"​ said the researchers.

Vitamin D is produced in the skin on exposure to UVB radiation and can also be consumed in small amounts from the diet. However, recent studies have shown that sunshine levels in some northern countries are so weak during the winter months that the body makes no vitamin D at all, leading some to estimate that over half of the population in such countries have insufficient or deficient levels of the vitamin.

Increased skin pigmentation also reduces the effect of UVB radiation meaning darker skinned people are more at risk.

And this is evident in the new study, published in the Archives of Disease in Childhood​ (doi: 10.1136/adc.2006.098467), that concluded that Asian infants are eight times more likely to have deficient blood levels of the vitamin than white children of the same age.

Vitamin D deficiency can lead to a range of health problems, including rickets, poor tooth formation, convulsions, general ill health, and stunted growth. It has also been linked to an increased risk of certain cancers, cardiovascular disease, diabetes, and osteoporosis.

"Our results are also in agreement with recent reports highlighting the resurgence of rickets in the British Asian population,"​ wrote Zipitis.

Despite such worrying statistics, the authors said that health authorities have deemed the cost of primary prevention a needless expense, given that the overall levels of vitamin D deficiency in the population are low.

Such a policy has led to a decline in vitamin D supplementation, with only four per cent of babies given the supplement in 2000, compared with 12 per cent in 1995.

But it costs more to treat the consequences of the deficiency than it does to prevent its occurrence, said the authors.

The researchers also pointed out a flaw in current practice to remedy vitamin D deficiency, noting that many paediatricians were prescribing alphacalcidol, which is not licensed for primary deficiency, and not backed up clinical trials. Instead, vitamin D deficient children should be given ergocalciferol (vitamin D2) or cholocalciferol (vitamin D3).

"Taking into account the fact that none of the children had received initial vitamin supplementation, the higher cost of treating vitamin D deficient Asian children compared to primary prevention, and the morbidity associated with the condition, we propose that local health authorities provide funds to supplement all Asian children with seven micrograms per day of vitamin D for at least the first two years of their lives,"​ concluded Zipitis.

A note of limitations of this study should be made however since the population studied was of "low socioeconomic status", said the authors, which may make generalisation of such findings to other populations inaccurate.

The UK government Committee on Medical Aspects of Food and Nutritional Policy (COMA) does suggest that infants and young children should be given vitamin D supplements for at least the first two years of their lives.