Sunlight, UV-radiation, vitamin D and skin cancer: how much sunlight do we need?

Adv Exp Med Biol. 2008;624:1-15. doi: 10.1007/978-0-387-77574-6_1.

Abstract

Vtamin D is the sunshine vitamin for good reason. During exposure to sunlight, the utraviolet B photons enter the skin and photolyze 7-dehydrocholesterol to previtamin D3 which in turn is isomerized by the body's temperature to vitamin D3. Most humans have depended on sun for their vitamin D requirement. Skin pigment, sunscreen use, aging, time of day, season and latitude dramatically affect previtamin D3 synthesis. Vitamin D deficiency was thought to have been conquered, but it is now recognized that more than 50% of the world's population is at risk for vitamin D deficiency. This deficiency is in part due to the inadequate fortification of foods with vitamin D and the misconception that a healthy diet contains an adequate amount of vitamin D. Vitamin D deficiency causes growth retardation and rickets in children and will precipitate and exacerbate osteopenia, osteoporosis and increase risk of fracture in adults. The vitamin D deficiency has been associated pandemic with other serious consequences including increased risk of common cancers, autoimmune diseases, infectious diseases and cardiovascular disease. There needs to be a renewed appreciation of the beneficial effect of moderate sunlight for providing all humans with their vitamin D requirement for health.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Humans
  • Skin Neoplasms / etiology
  • Skin Neoplasms / prevention & control*
  • Sunlight / adverse effects*
  • Ultraviolet Rays / adverse effects
  • Vitamin D / biosynthesis*
  • Vitamin D Deficiency / prevention & control
  • Vitamins / biosynthesis

Substances

  • Vitamins
  • Vitamin D