The beneficial effects of higher (adequate) vitamin D status on bone growth and muscle strength in children and adolescents

Abstract

Vitamin D is chemically a seco-steroid, which acts biologically as a prohormone and requires two hydroxylation processes, first in liver and the other in kidney (for those functions related to bone) before becoming active. The primary function of vitamin D is thought to be the maintenance of calcium and phosphate homeostasis and skeletal integrity throughout life. Numerous epidemiological studies suggest that vitamin D deficiency and/or insufficiency are global problems for growing children and adolescents. Although it is well established that persistent severe vitamin D deficiency results in the development of rickets in children and osteomalacia in adults, it is now suggested that a low 25-hydroxyvitamin D concentration is not only a biochemical abnormality, but also associated with physiological, pathological and clinical signs of vitamin D deficiency, along with secondary hyperparathyroidism, and increased bone remodelling across the lifespan. A growing body of evidence indicates that higher and adequate vitamin D status in the body plays an important role in maintaining musculoskeletal integrity at any age. However, the adverse effects of vitamin D deficiency on bone mass has been studied extensively in the postmenopausal women and in the elderly with only a few studies in children and adolescents. Therefore, the review will discuss the current evidence pertaining to the relationships between vitamin D status and musculoskeletal health in children and adolescents.