Vitamin D: an essential component for skeletal health

Ann N Y Acad Sci. 2011 Dec;1240:E1-12. doi: 10.1111/j.1749-6632.2011.06374.x.


Vitamin D deficiency is increasing worldwide. Ultraviolet rays are supposed to provide humans over 80% of our vitamin D requirement; the rest is received through diet and supplements. In addition to enhancing calcium absorption from the intestine and mineralization of the osteoid tissue, vitamin D has many other physiological effects, including neuromodulation, improving muscle strength and coordination, insulin release, immunity and prevention of infections, and curtailing cancer. Whether the increased incidence of vitamin D deficiency is related to increased incidences of nonskeletal disorders remains to be determined. Serum levels of 25-hydroxyvitamin [25(OH)D] above 30 ng/mL indicate vitamin D sufficiency. An additional 1,000 IU of vitamin D/day is sufficient for most lighter-skinned individuals, whereas an extra 2,000 IU/day is needed by the elderly and dark-skinned individuals to maintain normal 25(OH)D levels. Additional research is needed to clarify the relationship between vitamin D and the nonskeletal systems, nonclassic functions, and targets of vitamin D.

MeSH terms

  • Bone Diseases, Metabolic / prevention & control*
  • Bone and Bones / metabolism
  • Dietary Supplements
  • Humans
  • Receptors, Calcitriol / metabolism
  • Vitamin D / metabolism
  • Vitamin D / therapeutic use*
  • Vitamin D Deficiency / drug therapy
  • Vitamin D Deficiency / metabolism
  • Vitamin D Deficiency / prevention & control*


  • Receptors, Calcitriol
  • Vitamin D