OstroVit ® Vitamin D3 2000 IU is a dietary supplement in softgel capsules. This product was developed to supplement the diet of healthy adults. One serving of the dietary supplement contains 2000 IU of cholecalciferol. How does vitamin D3 work? Vitamin D3 , also known as cholecalciferol, is a steroidal organic chemical compound that belongs to the group of fat-soluble vitamins. contributes to the proper functioning of the immune system, helps in the proper absorption of phosphorus from the digestive tract, participates in maintaining the proper level of calcium in the blood, helps maintain health and teeth. Just take one capsule daily to achieve the beneficial effects claimed. A 60-pack of OstroVit will provide you with two months of supplementation with this valuable vitamin.