The ingredients of cod liver oil are vitamin A and vitamin D. Both vitamin A and vitamin D are fat-soluble vitamins, and the main ingredients of milk are protein and fat, so the ingredients of cod liver oil and milk powder do not interfere with each other, and the vitamin D in cod liver oil can promote the absorption of calcium in milk powder. Cod liver oil is the oil refined from the liver of sea fish. The main components of cod liver oil are fat-soluble vitamin A and vitamin D. In addition to this, gelatin, purified water and glycerin are added. Cod liver oil is used for the prevention and treatment of vitamin A and D deficiencies, such as rickets, night blindness and pediatric hand and foot convulsions. The main function of vitamin A is to maintain normal growth, reproduction, vision, epithelial tissue soundness and anti-infection immunity of the body. The main function of vitamin D is to promote the absorption of calcium and phosphorus by the small intestinal mucosa; to promote the reabsorption of calcium and phosphorus by the renal tubules. Doctors generally recommend that babies begin to supplement cod liver oil half a month after birth, starting with one drop per day, then gradually increasing to a maximum of five drops. The best time to take cod liver oil is in the morning after drinking milk, and it is best to take your baby to the sun after eating cod liver oil, so that it can be absorbed better.