Bio-D3 Plus Soft Gelatin Capsule is a combination of calcium that plays a very important role in the body. It is necessary for normal functioning of nerves, cells, muscles and bones. If there is not enough calcium in the blood, then the body will take calcium from bones, thereby weakening bones. Thus, the intake of calcium is necessary to keep the bones strong. Alfacalcidol increases the intestinal absorption of calcium and helps the body use calcium and phosphate to maintain healthy bones.