Updated: Apr 17, 2019

Most of us have heard of antioxidants, the term has been around for a long time. We are told to eat antioxidant rich food, you can find antioxidant supplements in pharmacies and health food stores, and they are heavily marketed as beneficial to our health. However, very few people actually know what they are and how they work. Should we be paying more attention to them? Should we all be buying antioxidant supplements? Read on to find out...

Antioxidants are substances that are thought to prevent and delay certain types of cell damage. To properly understand what they do, we must first understand free radicals, a term many will have heard of, but don’t truly understand.

What are free radicals?

Cells in our body become damaged every day. Some of this damage is caused by naturally occurring processes in the body, such as the metabolism of food or by exercising, but this cell damage can also occur when we are exposed to toxins. Whatever the reason, the result is that cells suffer from oxidative stress. Taking you briefly back to your school science days, oxidative stress causes oxygen in the body to split into single atoms with unpaired electrons. Electrons like to be in pairs, so these atoms, called free radicals, scavenge the body to seek out other electrons so that they can become a pair. This causes damage to cells and DNA. Once a free radical is formed, it creates a domino effect, creating many more free radicals as a result.

Despite this, it is worth keeping in mind that free radicals also serve important functions that are essential for our survival. For example, your body’s immune cells use free radicals to kill bacteria that try to infect us.

As with so many things in the body, we need a certain balance. We need the right amount of free radicals, and the right amount of antioxidants to keep them in check. When this balance gets disrupted, things can start to go wrong.

What are the effects of free radical damage?

Our bodies have defences against free radicals, but free radicals are highly unstable molecules, so when these defences are outweighed by the amount of free radicals roaming the body, they can cause lasting harm and even cell death.

Oxidative stress and an abundance of free radicals can:

  • damage DNA, leading to cancer

  • compromise cell walls, allowing substances into the cell that aren’t supposed to be there

  • make cholesterol stick to blood vessels, causing blockages

It has also been linked to several diseases including cardiovascular disease, diabetes, Parkinson’, Alzheimer’s disease, and eye diseases such as cataracts and age related macular degeneration. This cell damage is also thought to contribute to, or accelerate, the ageing process.

How can we control the amount of free radical damage in our bodies?

There are two main answers this question. One is to minimise your exposure to certain environmental and lifestyle factors, and the other is thought to be antioxidants. Let’s start with antioxidants.


Antioxidants come in many different shapes and sizes, but the quality they all seem to share is that they are able to neutralise free radicals, either by donating electrons making them more stable, or degrading them, rendering them harmless.

Whatever the mechanism it uses, an antioxidant seems to help protect the body from damage by interrupting the destructive effects of free radicals and the damage they cause. So for optimum health, a good dietary intake of antioxidants is essential. The good news is that antioxidants are found in many everyday foods!

Plant foods provide the widest diversity of antioxidants. Often the most colourful foods have the most potent antioxidants, so think berries, plums, grapes, green leafy vegetables such as broccoli, spinach and kale, capsicum, carrots, sweet potatoes, beetroot, to name just a few.

Meat products and fish also contain antioxidants, but in smaller amounts compared to fruits and vegetables. They are also plenty of other good sources including, green tea, coffee, dark chocolate, cinnamon, sunflower seeds and nuts.

Studies show that getting your antioxidants from food has a better effect on reducing cell damage from free radicals, however if you are unable to follow a healthy diet, it is also possible to use supplementation. Please note though, that more is not better in this case. High doses of antioxidant supplementation can have toxic effects, and may even have the opposite effect, causing further cell damage. So a low dose antioxidant or a quality multivitamin is the best strategy if you feel your diet is lacking.

Environmental and lifestyle factors

As I mentioned earlier, free radicals are also a result of exposure to toxins. These include:

  • air pollution

  • smoking or exposure to cigarette smoke

  • alcohol

  • high blood sugar levels

  • consuming large amounts of bad fats

  • medications

  • unprotected exposure to the sun

  • radiation

  • infections caused by bacteria, funghi or viruses

  • tissue damage caused by intense and prolonged exercise

So, as well as including plenty of antioxidant rich foods and drinks in our diets, if we can reduce our exposure to these toxins, we can reduce the effects the free radicals have on our body.

Food for thought if we want to keep our bodies (inside and out) young for as long as possible...