What is it? USDA Organic and vegan vitamin D tablets made from lichen. Each serving contains 2,000 IU of vegan vitamin D3 and includes organic sunflower lecithin to enhance absorption. What’s it for? Vitamin D has several important health benefits, with fortifying bone health and maintaining a healthy immune system being the most well-known. Adequate amounts of Vitamin D can regulate the absorption of calcium and maintain healthy phosphorus levels in the blood.