25-hydroxy Vitamin D2 (25(OH)D2) is one of the two main forms of vitamin D measured in the blood, the other being 25-hydroxy Vitamin D3. While Vitamin D3 is typically produced in the skin through sunlight exposure and obtained from animal-based sources, Vitamin D2 comes from plant-based sources and supplements. 25(OH)D2 is converted in the liver from ergocalciferol (Vitamin D2) and indicates the body's intake of this form of the vitamin. It plays a role in calcium and phosphate metabolism, immune function, and overall bone health. Although Vitamin D2 is less potent and has a shorter half-life than Vitamin D3, both forms contribute to total vitamin D levels.
25(OH)D2 is derived from plant-based sources and some supplements, whereas 25(OH)D3 is produced in the skin through sunlight exposure and found in animal-based foods. D3 is generally considered more potent and longer-lasting in the body.
No, 25(OH)D2 is only part of the picture. Total vitamin D status is determined by adding both 25(OH)D2 and 25(OH)D3 values together.