Zinc, calcium and iron are essential trace elements for the human body, but there are no special requirements for the timing of zinc, calcium and iron supplementation, which can be taken at different times of the day. Zinc deficiency may lead to anorexia, paranoia or omnivory, mouth ulcers, damaged wounds, decreased immunity, poor growth and development of children, increased pregnancy reactions, male infertility, etc. Calcium deficiency can lead to rickets, “X”-shaped legs, “O”-shaped legs and delayed intellectual development in children; pregnant women are prone to limb weakness, frequent cramps and dizziness, which also affect the health of the fetus; elderly people can suffer from lumbar spine and cervical spine pain, hunchback, reduced height, insomnia and irritability. etc. Iron deficiency can easily lead to anemia and affect children’s growth and development, motor development and immune function. Therefore, the supplementation of zinc, calcium and iron is crucial to the human body. Calcium, iron and zinc deficiencies are most prominent among children in China, and as they are essential elements for the growth and intellectual development of children, parents can take their children to the pediatrician or endocrinologist regularly for proper supplementation according to medical advice.