Vitamin D Supplements Lower the Risk for Fractures in Physically Active Adolescent Girls
Physically active adolescent girls who are engaged in high impact sports activities are at risk for stress fractures. However, this risk may be reduced when vitamin D supplements are taken. Compared to the regular intake of either calcium or dairy products, the intake of vitamin D supplements seem to have more significant effects in preventing bone fractures, as the results of the Growing Up Today Study shows.
The study included more than 6000 American adolescents aged 9-15, who were assessed by using a food frequency questionnaire every 1-2 years between 1996 and 2001. Data showed that among these girls, almost 4% developed stress fractures, 90% of which were caused by sports activities (mostly high-impact sports) done at least an hour a day.
Results show that girls who took an average of 1,182 mg of calcium or consumed three or more servings per day of dairy products were no less likely to develop stress fracture than those who did not take them. However, girls who took an average of 600 IU of vitamin D supplements (recommended daily allowance of vitamin D) appeared to be protected from suffering from fractures compared to girls who did not take them. Even those girls who took lesser doses of vitamin had lesser chances of getting fractures compared to those who did not.
The authors clarify that taking dairy products and calcium supplements are important to bone health, but for active girls, the requirement for vitamin D may be greater in preventing fractures due to weight-bearing activities that overuse and stress the bones.
Sources:
Phend, C. Vitamin D Key to Girls’ Bone Health. MedPage Today. Accessed 4/24/12.
Sonneville KR, et al. Vitamin D, calcium, and dairy intakes and stress fractures among female adolescents. Arch Pediatr Adolesc Med 2012; DOI: 10.1001/archpediatrics.2012.5.