- Antioxidants protect your body from free radicals. A free-radical is an unstable atom.
- Free-radicals can cause damage to your body.
- Antioxidants can help prevent the health issues caused by free radicals.
- Your body makes antioxidants, but you can also get them from food and supplements.
What are antioxidants?
Antioxidants are substances produced by your body that play an important role in your health. They are also found in foods, and in vitamin and mineral supplements. There are many different types of antioxidants.
Why are antioxidants important?
Many chemical reactions take place inside the cells in your body. Sometimes, these form by-products known as free radicals. Free radicals have important roles in your body. Some are used by your body’s immune system to attack viruses or bacteria.
However, if free radicals build up in your body, they can cause ‘oxidative stress’. This can damage your cells and impact your health.
Oxidative stress can damage your:
- eyes — causing cataracts and macular degeneration
- heart — causing hypertension (high blood pressure) and heart failure
- brain — causing Alzheimer’s disease and Parkinson’s disease
- joints — causing arthritis
- lungs — causing asthma and chronic bronchitis
- kidneys — causing kidney failure
Antioxidants are able to prevent the negative effects of these free radicals by neutralising them.
Can antioxidants prevent health issues?
Antioxidants are thought to help stop the health issues caused by free-radicals.
Research continues to increase our understanding of the effects of antioxidants against illness. Antioxidant supplements aren’t recommended to stop disease.
It’s still important to avoid other things that can damage your body, such as:
Which antioxidants are found in food?
Antioxidants are found in a variety of foods. For example:
- Vitamin C is found in citrus fruits, tomatoes and green vegetables.
- Vitamin E is found in plant oils, cereals, meat, eggs and fruits.
- Lycopene is primarily found in tomatoes and orange or red coloured fruits and vegetables.
- Omega-3 can mostly be found in seafood.
- Flavonoids are found in green tea, fruits, cocoa (chocolate), soybeans and vegetables.
- Selenium is found in nuts, vegetables, seafood and meat.
- Lutein and zeaxanthin are mostly found in green vegetables.
Why should I get my antioxidants from food?
You should aim to get all your nutrients, including antioxidants, from healthy foods rather than from supplements. People who eat a healthy diet generally get all their nutrients from their food.
Research suggests that antioxidants taken as supplements are less effective at combating heart disease and some cancers. Supplements don’t make people healthier.
However, antioxidant supplements can be useful if you:
- cannot access a variety of foods due to your location or income
- cannot digest foods properly due to gastrointestinal disorders
Your body needs a variety of antioxidants
No single antioxidant does everything. You need a variety.
When you eat many types of plant foods, you get a total package of antioxidants. There are hundreds of antioxidants in the foods recommended by the Australian dietary guidelines.
Too many antioxidants can be harmful
High doses of some antioxidant supplements can be harmful. For example, they can oppose the effects of some medicines. If you are on any medicines, make sure you ask your doctor about taking antioxidant supplements.
Resources and support
You can find out more about antioxidants and healthy eating by visiting the Australian Dietary Guidelines website.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available 24 hours a day, 7 days a week.
Learn more here about the development and quality assurance of healthdirect content.
Last reviewed: October 2022