Antioxidants are compounds in foods that neutralise free radicals. Oxidation in the human body produces chemicals called 'free radicals'. These chemicals have been linked to diseases such as heart and liver disease and cancer.
The process of oxidation in the human body damages cell membranes and other structures including cellular proteins, lipids and DNA. When oxygen is metabolised, it creates ‘free radicals’ which steal electrons from other molecules, causing damage.
The body can cope with some free radicals and needs them to function effectively. However, an overload of free radicals has been linked to certain diseases, including heart disease, liver disease and some cancers. Oxidation can be accelerated by stress, cigarette smoking, alcohol, sunlight, pollution and other factors.
Antioxidants and free radicals
Antioxidants are found in certain foods that neutralise free radicals. These include the nutrient antioxidants, vitamins A, C and E, and the minerals copper, zinc and selenium. Other dietary food compounds, such as the phytochemicals in plants and zoochemicals from animal products, are believed to have greater antioxidant effects than either vitamins or minerals. These are called the non-nutrient antioxidants and include phytochemicals, such as lycopenes in tomatoes, and anthocyanins found in cranberries.