Photosynthesis of previtamin D3 in human skin and the physiologic consequences

Science. 1980 Oct 10;210(4466):203-5. doi: 10.1126/science.6251551.


Photosynthesis of previtamin D3 can occur throughout the epidermis in the dermis when hypopigmented Caucasian skin is exposed to solar ultraviolet radiation. Once previtamin D3 is formed in the skin, it undergoes a temperature-dependent thermal isomerization that takes at least 3 days to complete. The vitamin D-binding protein preferentially translocates the thermal product, vitamin D3, into the circulation. These processes suggest a unique mechanism for the synthesis, storage, and slow, steady release of vitamin D3 from the skin into the circulation.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Carrier Proteins / metabolism
  • Cholecalciferol / biosynthesis*
  • Cholestadienols / biosynthesis*
  • Dose-Response Relationship, Radiation
  • Hot Temperature
  • Humans
  • Isomerism
  • Photochemistry
  • Rats
  • Skin / cytology
  • Skin / metabolism*
  • Ultraviolet Rays
  • Vitamin D / metabolism
  • Vitamin D-Binding Protein


  • Carrier Proteins
  • Cholestadienols
  • Vitamin D-Binding Protein
  • Vitamin D
  • Cholecalciferol
  • previtamin D(3)