TY - JOUR
T1 - Winter vitamin D3 supplementation does not increase muscle strength, but modulates the IGF-axis in young children
AU - Mortensen, Charlotte
AU - Mølgaard, Christian
AU - Hauger, Hanne
AU - Kristensen, Michael
AU - Damsgaard, Camilla Trab
N1 - CURIS 2019 NEXS 158
PY - 2019/4/1
Y1 - 2019/4/1
N2 - Purpose: To explore whether muscle strength, the insulin-like growth factor axis (IGF-axis), height, and body composition were associated with serum 25-hydroxyvitamin D [25(OH)D] and affected by winter vitamin D supplementation in healthy children, and furthermore to explore potential sex differences. Methods: We performed a double-blind, placebo-controlled, dose–response winter trial at 55ºN. A total of 117 children aged 4–8 years were randomly assigned to either placebo, 10, or 20 µg/day of vitamin D 3 for 20 weeks. At baseline and endpoint, we measured muscle strength with handgrip dynamometer, fat mass index (FMI), fat free mass index (FFMI), height, plasma IGF-1, IGF-binding protein 3 (IGFBP-3), and serum 25(OH)D. Results: At baseline, serum 25(OH)D was positively associated with muscle strength, FFMI, and IGFBP-3 in girls only (all p < 0.01). At endpoint, baseline-adjusted muscle strength, FMI and FFMI did not differ between intervention groups. However, baseline-adjusted IGF-1 and IGFBP-3 were higher after 20 µg/day compared to placebo (p = 0.043 and p = 0.006, respectively) and IGFBP-3 was also higher after 20 µg/day compared to 10 µg/day (p = 0.011). Children tended to be taller after 20 µg/day compared to placebo (p = 0.064). No sex interactions were seen at endpoint. Conclusions: Avoiding the winter-related decline in serum 25(OH)D may influence IGF-1 and IGFBP-3 in children. Larger trials are required to confirm these effects, and the long-term implication for linear growth.
AB - Purpose: To explore whether muscle strength, the insulin-like growth factor axis (IGF-axis), height, and body composition were associated with serum 25-hydroxyvitamin D [25(OH)D] and affected by winter vitamin D supplementation in healthy children, and furthermore to explore potential sex differences. Methods: We performed a double-blind, placebo-controlled, dose–response winter trial at 55ºN. A total of 117 children aged 4–8 years were randomly assigned to either placebo, 10, or 20 µg/day of vitamin D 3 for 20 weeks. At baseline and endpoint, we measured muscle strength with handgrip dynamometer, fat mass index (FMI), fat free mass index (FFMI), height, plasma IGF-1, IGF-binding protein 3 (IGFBP-3), and serum 25(OH)D. Results: At baseline, serum 25(OH)D was positively associated with muscle strength, FFMI, and IGFBP-3 in girls only (all p < 0.01). At endpoint, baseline-adjusted muscle strength, FMI and FFMI did not differ between intervention groups. However, baseline-adjusted IGF-1 and IGFBP-3 were higher after 20 µg/day compared to placebo (p = 0.043 and p = 0.006, respectively) and IGFBP-3 was also higher after 20 µg/day compared to 10 µg/day (p = 0.011). Children tended to be taller after 20 µg/day compared to placebo (p = 0.064). No sex interactions were seen at endpoint. Conclusions: Avoiding the winter-related decline in serum 25(OH)D may influence IGF-1 and IGFBP-3 in children. Larger trials are required to confirm these effects, and the long-term implication for linear growth.
KW - Children
KW - IGF-1
KW - IGFBP-3
KW - Muscle strength
KW - Randomized controlled trial
KW - Vitamin D
U2 - 10.1007/s00394-018-1637-x
DO - 10.1007/s00394-018-1637-x
M3 - Journal article
C2 - 29450728
SN - 1436-6207
VL - 58
SP - 1183
EP - 1192
JO - European Journal of Nutrition
JF - European Journal of Nutrition
IS - 3
ER -