Cod liver oil is a dietary supplement derived from the liver of cod fish. It is rich in omega-3 fatty acids (EPA and DHA) as well as vitamins A and D, which support overall health. It is commonly used to promote bone health, support immune function, and maintain healthy skin, eyes, and cardiovascular health. The omega-3 content helps reduce inflammation, while vitamins A and D contribute to normal vision and calcium absorption. It is typically taken in liquid or capsule form as a nutritional supplement.