More on Vitamin D3 Sources

"At one time, Vitamin D-2 was added to milk. Vitamin D-2 is manufactured by exposing bacteria and algae to ultra-violet light. D-2 imparted a bitter taste to dairy products, and so was replaced by vitamin D-3."

"Basically D-3 always is derived from an animal. The sunlight reaction that converts 7-dehydrocholesterol to vitamin D-3 is a 'pure' chemical reaction that occurs in your skin in certain cells." 

Sources of D3:

Pig skin, sheep skin, raw fish liver, and pig brains.


  • Vitamin D1 (a molecular compound of lumisterol and vitamin D2)
  • Vitamin D2 (calciferol, ergocalciferol)
  • Vitamin D3 (cholecalciferol, activated 7-dehydrocholesterol)
  • Vitamin D4 (22:23-dihydroergocalciferol)
  • Calcitriol (1,25-dihydrocholecalciferol)

To read more on Vitamin D - visit our You Should Know - Vitamin D - Not All You Think It Is.