Vitamin D status of Year 3 children and supplementation through schools with fortified milk
AbstractObjectiveTo evaluate levels of vitamin D3and HDL-cholesterol (HDL-C), and the ratio of HDL-C to LDL-cholesterol (LDL-C), in schoolchildren receiving vitamin-D-fortified, fat-depleted, high-Ca milk in schools.DesignCross-sectional study of previously randomised schools receiving supplemental milk, compared with a matched control group.SettingLow-decile Year 1–6 schools in the Waikato region of New Zealand.SubjectsYear 3 children from either milk schools or control schools, consenting to blood sampling.ResultsFor eighty-nine children receiving supplementary daily milk, vitamin D3levels were significantly higher than in eighty-three control children matched for age, sex, body composition and ethnicity (mean (sd): 49·6 (15·8)v. 43·8 (14·7) nmol/l,P= 0·011), as were HDL-C levels (mean (sd): 1·47 (0·35)v. 1·35 (0·29) mmol/l,P= 0·024) and HDL-C:LDL-C (median: 0·79v. 0·71,P= 0·026). LDL-C levels were similar in both groups (mean (sd): 2·07 (0·55)v. 2·16 (0·60) mmol/l,P= 0·31). Of control children, 32/83 (20·2 %) of the milk group (Pearson’sχ2= 7·00,P= 0·008). Mean 25-hydroxyvitamin D (vitamin D3) levels in the milk group were still below the lower end of the recommended normal range (60 nmol/l).ConclusionsVitamin D3levels are low in low-decile Year 3 children in midwinter. Levels are improved with vitamin-D-fortified milk but still below the recommended range. HDL-C and HDL-C:LDL-C levels are improved in the milk-supplemented group. This supports the supply of vitamin-D-fortified, fat-reduced milk to schools.