Cod-liver oil is a yellow, fishy-smelling oil obtained from the livers of codfish. It contains large amounts of the vitamins A and D. At one time, many people took cod-liver oil to protect against vitamin A and D deficiencies. People who do not receive enough vitamin A may develop skin and eye problems. A lack of vitamin D can cause rickets, a disease that leads to deformed bones.
A balanced diet normally provides all the vitamins A and D a person normally requires. For example, fortified milk is high in both vitamins, and green and yellow vegetables are a good source of vitamin A. Yet cod-liver oil remains a popular dietary supplement in liquid or capsules. Cod-liver oil and other fish oils contain a special kind of fatty acid called omega-3, which many scientists believe can reduce a person’s risk for heart disease and other illnesses.
