WebMD – Antioxidants and Your Immune System: Super Foods for Optimal Health

They are vitamins, minerals, and other nutrients that protect and repair cells from damage caused by free radicals. Many experts believe this damage plays a part in a number of chronic diseases, including hardening of the arteries (atherosclerosis), cancer, and arthritis. Free radicals can also interfere with your immune system. So, fighting off damage with antioxidants helps keep your immune system strong, making you better able to ward off colds, flu, and other infections.