TY - JOUR
T1 - Vitamin D status and its determinants during autumn in children at northern latitudes
T2 - a cross-sectional analysis from the optimal well-being, development and health for Danish children through a healthy New Nordic Diet (OPUS) School Meal Study
AU - Petersen, Rikke A
AU - Damsgaard, Camilla T
AU - Dalskov, Stine-Mathilde
AU - Sørensen, Louise B
AU - Hjorth, Mads F
AU - Ritz, Christian
AU - Kjølbæk, Louise
AU - Andersen, Rikke
AU - Tetens, Inge
AU - Krarup, Henrik
AU - Astrup, Arne
AU - Michaelsen, Kim F
AU - Mølgaard, Christian
PY - 2016
Y1 - 2016
N2 - Sufficient summer/autumn vitamin D status appears important to mitigate winter nadirs at northern latitudes. We conducted a cross-sectional study to evaluate autumn vitamin D status and its determinants in 782 Danish 8-11-year-old children (55°N) using baseline data from the Optimal well-being, development and health for Danish children through a healthy New Nordic Diet (OPUS) School Meal Study, a large randomised controlled trial. Blood samples and demographic and behavioural data, including 7-d dietary recordings, objectively measured physical activity, and time spent outdoors during school hours, were collected during September-November. Mean serum 25-hydroxyvitamin D (25(OH)D) was 60·8 (sd 18·7) nmol/l. Serum 25(OH)D levels ≤50 nmol/l were found in 28·4 % of the children and 2·4 % had concentrations <25 nmol/l. Upon multivariate adjustment, increasing age (per year) (β -2·9; 95 % CI -5·1, -0·7 nmol/l), female sex (β -3·3; 95 % CI -5·9, -0·7 nmol/l), sampling in October (β -5·2; 95 % CI -10·1, -0·4 nmol/l) and November (β -13·3; 95 % CI -17·7, -9·1), and non-white ethnicity (β -5·7; 95 % CI -11·1, -0·3 nmol/l) were negatively associated with 25(OH)D (all P<0·05). Likewise, immigrant/descendant background was negatively associated with 25(OH)D, particularly in females (β -16·3; 95 % CI -21·9, -10·7) (P<0·001) (P interaction=0·003). Moderate-to-vigorous physical activity (MVPA) (min/d) (β 0·06; 95 % CI 0·01, 0·12), outdoor walking during school hours (min/week) (β 0·4; 95 % CI 0·1, 0·6) and intake of vitamin D-containing supplements ≥3 d/week (β 8·7; 95 % CI 6·4, 11·0) were positively associated with 25(OH)D (all P<0·05). The high proportion of children with vitamin D status below the recommended sufficiency level of 50 nmol/l raises concern as levels expectedly drop further during winter months. Frequent intake of vitamin D supplements was strongly associated with status. MVPA and outdoor activity during school hours should be investigated further in interventions to improve autumn vitamin D status in children at northern latitudes.
AB - Sufficient summer/autumn vitamin D status appears important to mitigate winter nadirs at northern latitudes. We conducted a cross-sectional study to evaluate autumn vitamin D status and its determinants in 782 Danish 8-11-year-old children (55°N) using baseline data from the Optimal well-being, development and health for Danish children through a healthy New Nordic Diet (OPUS) School Meal Study, a large randomised controlled trial. Blood samples and demographic and behavioural data, including 7-d dietary recordings, objectively measured physical activity, and time spent outdoors during school hours, were collected during September-November. Mean serum 25-hydroxyvitamin D (25(OH)D) was 60·8 (sd 18·7) nmol/l. Serum 25(OH)D levels ≤50 nmol/l were found in 28·4 % of the children and 2·4 % had concentrations <25 nmol/l. Upon multivariate adjustment, increasing age (per year) (β -2·9; 95 % CI -5·1, -0·7 nmol/l), female sex (β -3·3; 95 % CI -5·9, -0·7 nmol/l), sampling in October (β -5·2; 95 % CI -10·1, -0·4 nmol/l) and November (β -13·3; 95 % CI -17·7, -9·1), and non-white ethnicity (β -5·7; 95 % CI -11·1, -0·3 nmol/l) were negatively associated with 25(OH)D (all P<0·05). Likewise, immigrant/descendant background was negatively associated with 25(OH)D, particularly in females (β -16·3; 95 % CI -21·9, -10·7) (P<0·001) (P interaction=0·003). Moderate-to-vigorous physical activity (MVPA) (min/d) (β 0·06; 95 % CI 0·01, 0·12), outdoor walking during school hours (min/week) (β 0·4; 95 % CI 0·1, 0·6) and intake of vitamin D-containing supplements ≥3 d/week (β 8·7; 95 % CI 6·4, 11·0) were positively associated with 25(OH)D (all P<0·05). The high proportion of children with vitamin D status below the recommended sufficiency level of 50 nmol/l raises concern as levels expectedly drop further during winter months. Frequent intake of vitamin D supplements was strongly associated with status. MVPA and outdoor activity during school hours should be investigated further in interventions to improve autumn vitamin D status in children at northern latitudes.
U2 - 10.1017/S000711451500433X
DO - 10.1017/S000711451500433X
M3 - Journal article
C2 - 26563915
SN - 0007-1145
VL - 115
SP - 239
EP - 250
JO - British Journal of Nutrition
JF - British Journal of Nutrition
IS - 2
ER -