The effects of vitamin D supplementation on bone density in vitamin D insufficient teenagers: randomised controlled trial

Osteoporosis fractures are common, costly and cause significant death and disability. They may be reduced by improving the amount of bone laid down in childhood. Childhood vitamin D deficiency is common and is harmful for bone development. The use of vitamin D supplements in children to improve bone health needs further investigation. This study aims to determine what effect vitamin supplementation has on bone development in adolescents who have mild to moderate vitamin D deficiency. This will be tested through a placebo controlled randomised controlled trial of vitamin D supplementation in a sample of mild to moderately vitamin D deficient adolescents aged 15 to 17 years.