A fat-soluble vitamin, Vitamin D, especially the D3 form, has many functions necessary to human health. Vitamin D helps support bone health and teeth by enhancing the absorption of calcium and phosphorus.

Vitamin D is made in the human body from exposure to strong, noon sunlight for at least 15 minutes daily. In winter, however, Vitamin D supplements are crucial to helping the body manufacture Vitamin D. Testing for Vitamin D deficiency is a simple blood test at a doctor’s office.