What are anti-oxidants? Why are they added to fat and oil containing foods?

Anti-oxidants are the chemicals which are added to fat and oil containing foods to slow or delay the development of rancidity. Natural Anti-oxidants are ascorbic acid ad tocopherols whereas synthetic anti- oxidants include Butylated hydroxyanisole (BHA) and Butylated hydroxytoluene (BHT). Anti-oxidants can be nutrients as well as enzymes that are especially proteins that can assist in chemical reaction and prevent development such as cancer,heart attack and many other chronic diseases