Observations on the natural history of vitamin D deficiency amongst Asian immigrants.

The Asian community of Rochdale was examined for evidence of vitamin D deficiency in 1970 and again in 1980. There has been a striking improvement in the biochemical markers of vitamin D deficiency among Asian children, but little improvement was observed in the adults. Asian children born in the United Kingdom had higher serum 25 hydroxyvitamin D concentrations than migrant children. Prolonged residence in the United Kingdom and a long period of exposure to western customs was not associated with a better vitamin D status in the adults. The vitamin D status of this community was still markedly inferior to that of a white control group despite attempts to influence their dietary practices and habitual solar exposure. Vitamin D deficiency presents a continuing problem among first generation adult migrants, but a decreasing problem among children.