Beyond the established roles of vitamin D in bone and mineral homeostasis, we are becoming increasingly aware
of its diverse effects in skeletal muscle. Subjects with severe vitamin D deficiency or mutations of the vitamin D
receptor develop generalized atrophy of muscle and bone, suggesting coordinated effects of vitamin D in musculoskeletal
physiology. At a mechanistic level, vitamin D exerts wide-ranging effects in muscle and bone calcium
handling, differentiation and development. Vitamin D also modulates muscle and bone-derived hormones, facilitating
cross-talk between these tissues. In this review, we discuss emerging evidence that vitamin D regulates
bone and muscle in a direct, integrated fashion, positioning the vitamin D pathway as a potential therapeutic target
for musculoskeletal diseases.