Tips and advice

What are antioxidants?

Antioxidants are substances that can prevent, or delay cell damage caused by chemicals called free radicals.1 Free radicals are produced naturally in our bodies during exercise and when our body produces energy.1 We are also exposed to free radicals from environmental sources such as air pollution, radiation, and cigarette smoke.1 Free radicals are highly reactive and unstable which makes them prone to attacking other molecules and causing damage to the cells in our body.1 Antioxidants work to prevent damage by reacting with and neutralising them.

Why are antioxidants important?

At low to moderate levels, free radicals have beneficial roles in cellular processes and functioning of our immune system.1 However, excessive amounts of these unstable molecules can lead to a phenomenon known as oxidative stress.1 Oxidative stress damages cells, proteins, and DNA and has been linked to the development of several diseases, including:1






Autoimmune disorders


Cardiovascular disease


Neurodegenerative diseases (such as Alzheimer’s disease and Parkinson’s disease)

Antioxidants play a vital role in protecting our bodies against oxidative stress by keeping free radicals in check. They help to prevent damage to cells and tissues and can reduce the risk of chronic diseases.1

Types of antioxidants

Several different substances can act as antioxidants. Your body can make some of these antioxidants itself.2 These are known as endogenous antioxidants. The rest of the antioxidants needed by the body come from external (exogenous) sources, primarily from the diet.1 Three well-known dietary antioxidants include vitamins C and E, beta-carotene and selenium.1

How to incorporate antioxidants into your diet

One way of preventing the damaging effects of oxidative stress is to make sure you get enough antioxidants from your diet. Fruits and vegetables are the primary sources of dietary antioxidants.2 Other sources of antioxidants include nuts, seeds, whole grains, and certain types of meat and fish.2 

Good sources of the key antioxidants

Below are some of the main food sources of vitamin C, vitamin E, beta-carotene, and selenium. Consider including these foods into your diet to boost your antioxidant intake.  

Vitamin C

Good sources include oranges, blackcurrants, kiwifruit, mangoes, broccoli, spinach, capsicum and strawberries.2

Vitamin E

Good sources include vegetable oils, avocados, nuts, seeds, and whole grains.2


Good sources include pumpkin, mangoes, apricots, carrots, spinach and parsley.2


Good sources include Brazil nuts, seafood, offal, lean meat and whole grains.2

Boost your antioxidant intake with Ensure

Ensure provides complete, balanced nutrition with 28 essential vitamins and minerals, including antioxidants (vitamin C, E and selenium), zinc and copper to support immune health.3 Consider incorporating Ensure into your diet and boost your daily nutrition. 

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Food for Special Medical Purposes. Use only under medical supervision.

References: 1. Pham-Huy LA, et al. Int J Biomed Sci. 2008;4(2):89–96. 2. Better Health Channel. Antioxidants. Available at: Accessed: May 2023. 3. Ensure® Product Label.