Vitamin d3 is very important to the health of the body, which is directly related to its nature and efficacy. The role of vitamin d3 is mainly reflected in the following points. First, it can help the stomach absorb phosphorus and calcium and avoid corresponding problems in the intestine. Second, it can also promote the absorption of calcium and phosphorus by the kidney and ensure the health of the kidney. Third, the role of vitamin d3 is to improve the body's immunity, because it has a good effect on blood health. Fourth, the role of vitamin d3 is to protect bone health, especially to prevent rickets, which is the main reason why most babies take vitamin d3. What is provided above is the function of vitamin d3. In fact, its efficacy is very comprehensive. In addition to the above functions, its function is also reflected in the prevention of various cancers, such as breast cancer. The main function of vitamin d3 is to promote calcium to be better absorbed by human body.