Children aged 3~6 years usually do not need to supplement cod liver oil, if there is malnutrition, picky eating, anorexia and other conditions, can be appropriate supplementation of cod liver oil, but should be used under the guidance of a doctor. Cod liver oil mainly contains vitamin A and vitamin D, can be used to prevent rickets, night blindness and other vitamin deficiency diseases, generally advocate that the baby preventive supplementation of cod liver oil to the age of three years can be, after the age of three years can not continue to take. In addition, for children aged 3 to 6 years old, their daily diet or infant formula food, two vitamin content is already enough. If the child has malnutrition, picky eating, anorexia and other conditions, need to eat cod liver oil, should be strictly controlled amount, under the guidance of the doctor to take, so as not to cause vitamin overdose poisoning and other hazards. At the same time, if there is a rash, diarrhea, vomiting and other adverse reactions, it should be promptly discontinued. In short, children aged 3 to 6 years old need to eat cod liver oil depending on the situation, in addition, more sunshine, appropriate participation in outdoor activities, help the absorption of nutrients.