Recent research has shown that vitamin D is important to every cell and tissue throughout the body. From proper immune function and bone density to heart health and mood disorders, vitamin D is critical for optimal health.

You should know your vitamin D blood level. Life Extension® offers a reliable vitamin D blood test at a fraction of what most commercial blood labs charge. Optimal blood levels of vitamin D are often far greater than the standard reference range. The only way to achieve an optimal level is through proper supplementation.