Dietary and lifestyle factors affecting plasma vitamin D levels in Asian children living in England

Abstract

Objective: To determine the vitamin D status of a sample of young Asian children living in England by measurement of plasma 25-hydroxycholecalciferol levels; to relate biochemical measurements with parameters of diet, lifestyle and iron status in this population.

Design: The 'Infant Feeding in Asian Families' survey covered infants born to mothers of Bangladeshi, Indian or Pakistani origin, plus a sample of children born to White mothers in 41 local authority areas. The current study describes vitamin D values in a sub sample of Asian children from that survey.

Setting: Forty-one local authority areas which covered 95% of the Asian population at the time of the 1991 Census and include areas with the highest and lowest density of Asians.

Subjects: Seventy-one percent (2382) of mothers who were originally eligible were interviewed on four occasions up to the time their infant was 15 months. One thousand, seven hundred and thirty-eight of these children were followed up for this current study. Of these 618 had a blood sample analysed for vitamin D.

Outcome measures: Previous day's food intake, normal dietary intake, indicators of iron status and plasma vitamin D levels.

Results: Plasma vitamin D values are lower in the three groups of Asian children than values reported for children of a similar age in the National Diet and Nutrition Survey. Between one third and a half of children with a low haemoglobin also had low plasma vitamin D values; there was a significant association between failure to take a vitamin supplement, chapati consumption and low vitamin D values.

Conclusions: It is particularly important that pre-school Asian children receive a vitamin D supplement. Children with low haemoglobin values should be screened for vitamin D deficiency.