After the iron is absorbed by the human body, it will be oxidized into stable ferric iron, which is not conducive to human absorption, while vitamin C is a reducing agent with antioxidant function.

Most of the iron exists in red blood cells in the form of hemoglobin, which is mainly responsible for the transportation of oxygen for metabolism. The synthesis of hemoglobin will be affected if the supply of iron is insufficient,and severe cases will lead to anemia. Vitamin C can affect the absorption of iron in the intestines and also affect the distribution of iron in the human body.