Vitamin D comes in two forms: D2 and D3. Of the two, D3 is more bioactive. The body synthesizes vitamin D3 from cholesterol and sunlight; which makes it difficult to obtain adequate amounts of vitamin D during cloudy or winter months. In the body, vitamin D is responsible for maintaining normal blood levels of calcium and phosphorus, and helping to build strong bones. Vitamin D may also contribute to the overall health of the cardiovascular system. It works with other vitamins, minerals and hormones to promote bone mineralization. Research shows that vitamin D may help support a healthy immune system by regulating lymphocyte function, cytokine production and macrophage activity. Studies also show that Vitamin D may improve seasonal mood disorders.
2,000 IU Vitamin D3 per tablet (500% Daily Value).