Antioxidants are molecules that help neutralize free radicals, which are unstable atoms that can cause cellular damage. They are vital for health as they contribute to the prevention of various chronic diseases, including heart disease and cancer. Common antioxidants include vitamins A, C, and E, as well as minerals like selenium. These compounds play a crucial role in reducing oxidative stress and inflammation in the body. By incorporating foods rich in antioxidants, such as fruits and vegetables, individuals can enhance their immune system and promote overall well-being, highlighting their essential role in preventive health strategies.