Vitamin A: Preformed vitamin A, a fat-soluble vitamin, is more readily absorbed than the precursors to vitamin A, the carotenoids, which need to be converted to a more usable form before they can be utilized by the body. Vitamin A is a powerful antioxidant and it plays an important role in our immune system and in the formation of healthy epithelial tissue—the skin, glands, mucous membranes, organ linings, and the entire length of the respiratory, gastrointestinal, and genitourinary tracts.
Vitamin D: Vitamin D is also a fat-soluble vitamin that plays a dual role as both a vitamin and a hormone. Vitamin D is a great regulator of calcium and phosphorus metabolism. Without vitamin D, the body cannot properly absorb calcium and the bones and teeth become soft and poorly mineralized.
