Antioxidants

The main antioxidants are vitamins A, C, E, beta-carotene and selenium, along with phytochemicals, such as lycopene and lutein.

Antioxidants are found in a range of foods - nuts, wholegrains, some meat, poultry & fish and particularly in brightly-coloured fruits and vegetables. Some antioxidant rich foods are:

  • Citrus fruits
  • Berries – cranberries, blueberries, blackberries
  • Tomatoes, including canned tomatoes
  • Colourful vegetables – eg. red cabbage, orange capsicum
  • Onions
  • Potatoes
  • Walnuts, hazelnuts, brazil nuts
  • Tea, coffee and cocoa

Antioxidants work by slowing or even preventing the harmful activity of ‘free radicals’ in our bodies. Free radicals are all around us everyday – pollution, cigarette smoke and sun exposure. But they are also formed from one of life’s necessities – oxygen. When we breath in oxygen, a tiny amount is not properly converted, leaving an oxygen molecule with a free electron, or a free radical. These free radicals damage almost any cell and are responsible for a major part of the ageing process, as well as the beginnings of health problems like cancer and heart disease.

People living in countries with a high intake of fruit and vegetables live longer and are healthier with lower rates of heart disease and cancers. One of the reasons for this is the wide range of antioxidants which are present in fruit and vegetables. A 2007 report from the World Cancer Research Fund found people who ate more fruit and non-starchy vegetables had a lower risk of developing several cancers, including mouth, throat, oesophagus and stomach.

Research has shown fruits and vegetables interact when eaten together, producing a more powerful antioxidant effect than taking a large dose of the antioxidant in a supplement.

Taking an antioxidant supplement can not necessarily replace the action of antioxidant-rich foods – in fact, it may be harmful. For example, research on smokers found taking beta-carotene supplements increased the risk of dying from lung cancer. A review of research trials using antioxidant supplements found an increased risk of mortality with beta-carotene supplements, and possible Vitamin E and vitamin A (but not vitamin C and selenium). The authors suggested that current evidence does not support the use of antioxidant supplements in the general population or in patients with various diseases

So, the safest and most effective source of antioxidants is food.

The New Zealand Ministry of Health recommends eating plenty of vegetables and fruit, at least five servings each day. Visit our fruit & vegetable page for more information.

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Page reviewed June 2013