When exposed to sunlight, our bodies will naturally make vitamin D3. This process happens when ultraviolet B (UVB) radiation from the sun triggers the 7-dehydrocholesteol to produce D3. • Vitamin D is one of the body's most important vitamins, helping it with a variety of tasks: Vitamin D contributes to the normal function of the immune system and is very important for the body's structural system, maintaining normal bone and muscle function.
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