Vitamin D3 May Be More Potent than Vegan Vitamin D2

Animal-derived vitamin D3 (cholecalciferol) may be almost 10 times more potent than the plant-derived, vegan-friendly vitamin D2 (ergocalciferol), according to research conducted through Creighton University and the Medical University of South Carolina.

The study in the Journal of Clinical Endocrinology & Metabolism compared vitamin D uptake in 20 healthy men over 28 days following a single dose of 50,000 IU of vitamin D2 or vitamin D3. Serum vitamin D and 25-hydroxyvitamin D served as vitamin D markers.

On day three of observations, researchers noticed comparable absorption levels for both vitamin D forms; however, by day 14, vitamin D3 levels were just peaking and vitamin D2 levels had already fallen back to baseline.

In calculating area under the curve, the researchers concluded that a differential in vitamin D3 to vitamin D2 could be as large as 9.5 to 1.

The results of the study support previous research declaring vitamin D3 as more potent than vitamin D2, including a 1998 study in the American Journal of Clinical Nutrition.

Vitamin D3 can be obtained through sun exposure, but because vitamin D is so often supplemented into foods, beverages, and dietary supplements, understanding the potency of vitamin D forms is important. This is especially true for strict vegan consumers who avoid vitamin D3, often derived from sheep’s wool.

The study was supported by research funds from Creighton University and the Medical University of South Carolina.