Vitamin A, B vitamins, vitamin C, vitamin D, and vitamin E have different roles and functions. For example, treating eye diseases and preventing malnutrition. 1. Vitamin A: Vitamin A is an important component of visual cells, which is very important for the health of the eyes and mucous membranes. Vitamin A deficiency can be used for night blindness, dry eye disease, corneal chondromalacia, skin roughness and so on. 2. B vitamins: B vitamins are widely involved in metabolism in the human body, with a wide variety of different roles. B vitamins can effectively prevent and treat malnutrition, anorexia, athlete’s foot, pellagra, etc., and are very helpful for the protection of the skin, the digestive tract, and the nervous system. 3. Vitamin C: It has good antioxidant properties, prevents cancer, stroke and cardiovascular diseases, and also promotes the absorption of trace elements, improves myocardial function, promotes wound healing, and prevents melanin deposition. 4. Vitamin D: can promote the body’s absorption of calcium and phosphorus, can promote the growth and calcification of bones, promote dental health, vitamin D deficiency can lead to rickets, hand and foot twitching, chondromalacia and so on. 5. Vitamin E: also known as tocopherol, is a substance related to fertility, can promote male reproductive function, improve male sperm vitality, improve female hormone secretion, prevent miscarriage, male infertility, etc. If it is a preterm baby, the insufficiency of tocopherol will lead to severe anemia. For patients with vitamin A, B vitamins, vitamin C, vitamin D, vitamin E deficiency, it is recommended that standardized treatment should be carried out under the guidance of a doctor.