Here we have added references and links to research papers and reports we have reviewed. This does include a paper supporting Vitamin D2. We hope you find the references useful.
What is Vitamin D3?
Vitamin D3, Cholecalciferol, is the naturally occurring form of the D Vitamin. It is produced by the human body when skin makes contact with direct sunlight.
What is Vitamin D2?
Vitamin D2, Ergocalciferol, is a derivative of ergosterol. This is the form found in most vegetarian and vegan Vitamin D supplements.
Research suggests Vitamin D3 is more potent
We reviewed many research papers and the majority opinion in the Scientific community is that Vitamin D3 is more efficacious than D2. There is some research to the contrary, but after studying the research available and consulting many industry experts, our conclusion is the evidence suggests that Vitamin D3 is superior to Vitamin D2. Here are some research quotes and references to papers we have reviewed:
“The scientific community is aware that these molecules are not equivalent”
Lisa A Houghton and Reinhold Vieth
>> Am J Clin Nutr October 2006 vol. 84 no. 4 694-697
“Vitamin D2 potency is less than one third that of Vitamin D3”.
Laura A. G. Armas, Bruce W. Hollis and Robert P. Heaney
>> The Journal of Clinical Endocrinology & Metabolism November 1, 2004 vol. 89 no. 11 5387-5391
“Vitamin D3 ’87 percent more potent’ than D2”
Stephen Daniells, Nutra Ingredients Magazine website article
>> Nutra Ingredients Magazine article
We do acknowledge there is some published research offering results to counter the overall verdict that D3 is superior to D2:
“Vitamin D2 is as effective as Vitamin D3”
Michael Holick et al
>> J Clin Endocrinol Metabolism 93: 677–681, 2008
Our main aim is to give Vegetarians and Vegans the choice of a suitable Vitamin D3. We always welcome new data and research on Vitamin D3 or D2.
If we come across new data or interesting studies, we will post details on our blog and community pages.