1. What is cod liver oil? Cod liver oil is a natural nutritional health product extracted from deep-sea fish liver. It is rich in a variety of unsaturated fatty acids, vitamins A, D and other nutrients. Among them, vitamins A and D play an important role in human body growth and development, immunity, vision protection and other aspects. 2. Why do babies need to supplement cod liver oil? In the first 6 months after birth, babies are prone to vitamin D deficiency due to the low vitamin D content in breast milk or formula. Vitamin D deficiency can affect the baby\’s bone development and immunity