Free radicals and active oxygen species are toxic as they can oxidize biomolecules leading to cell death and tissue injury. From another point of view; lipid oxidation is also a major cause of chemical spoilage in foods. It leads to many undesirable changes in flavour, texture and nutritional value in foods. Therefore, food processors must control lipid oxidation in their products as much as possible. Milk proteins, caseins and whey proteins, have important roles in preventing lipid oxidation and maintaining milk quality. Creating a market for the use of milk proteins as antioxidants would not only decrease spoilage of foods by lipid oxidation and improve human health but would also increase milk protein utilization and decrease whey disposal costs.