Antioxidants are substances that can prevent or slow damage to cells caused by free radicals, unstable molecules that the body produces as a reaction to environmental and other pressures. They are sometimes called free-radical scavengers".

They can protect against the cell damage that free radicals cause, reducing the risk of many non-communicable diseases. Therefore, the option that best describes the role of antioxidants is that they neutralize the free radicals produced in the body during metabolism.