Vitamin D2 Supplements May Deplete More Effective Vitamin D3

Choosing the wrong type of vitamin D supplement may do more harm than good, researchers say.

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Millions of people taking vitamin D2 supplements to boost their health may be inadvertently depleting their body’s stores of the more potent form of the vitamin, according to recent research from the University of Surrey.

The findings challenge common supplementation practices, particularly those of the winter months when sunlight exposure is limited and many people turn to supplements to maintain vitamin D levels.

Why D2 May Lower D3 Levels

There are two main types of vitamin D supplements available: vitamin D2 and vitamin D3, with D3 considered the more effective form of the vitamin for maintaining health. Vitamin D2 can be obtained only through diet and supplementation, while vitamin D3 is both available in supplements and naturally synthesized in the skin when exposed to sunlight.