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Free radicals and antioxidants are always in your body. But did you know that both can fight disease and cause it? Here’s a simple explanation of what free radicals and antioxidants are, what they do, where they come from, and what you should eat and drink to be healthy.

I see it in the news, in magazines, and splashed all over beauty ads: Free radicals are bad. Antioxidants are good.

So I decided to do some digging to make right choices about what I eat and put on my skin, I found some very interesting facts about antioxidants and free radicals.

Don’t forget to grab your free antioxidant grocery list by clicking on the picture below:

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I promised you an easy-to-understand breakdown of where free radicals come from, what they do to the body, and what role antioxidants really play here.

Let’s start with the very basics of the human body: atoms.

You are made of atoms

Your body is made up of about 7 billion billion billion atoms! You’re about 65% hydrogen, 24% oxygen and 10% carbon atoms.

But what are atoms?

Atoms are tiny particles that make up all matter.

Atoms consist of protons, neutrons and electrons. The center of the atom is where protons and neutrons live. Together they are called the ‘nucleus’.

Electrons spend their days flying around the nucleus of an atom, like little suns. Their path around the nucleus is called an orbit. It’s important to know that electrons like to be in pairs (twos) in their orbit.

Atom structure diagram


What are free radicals?

One of the many things your body does to keep you alive and healthy is a process called oxidation. During this process, oxygen is split into atoms with unpaired electrons.

When electrons don’t have a partner electron in their orbit, they are ‘unstable’. An unstable atom is a called a free radical.

Free radical structure with unpaired electrons

Free radicals want to pair with other electrons, so they try to steal electrons from molecules around them.

What do antioxidants do?

Antioxidants can give an electron to a free radical, without becoming an unstable free radical themselves.

Antioxidant giving electron to free radical 2

Once an antioxidant gives an electron to a free radical, the free radical becomes stable and the antioxidant is neutralized or excreted by the body.

In this way, antioxidants balance out free radicals in the body.

How are free radicals formed?

Your body is always making free radicals as a waste product of many natural bodily functions.

Your body creates free radicals when it processes the air you breath, the things you eat and drink, the medicines you take, and whatever enters through your skin.

Are free radicals always bad for you?


In fact, you could die without them! Free radicals help us with essential chemical processes and they help us fight disease.

“… free radicals are essential to life … The body’s ability to turn air and food into chemical energy depends on a chain reaction of free radicals. Free radicals are also a crucial part of the immune system, floating through the veins and attacking foreign invaders.”

Source: Food at Work, Christopher Wanjek, 2006

Like most things, free radicals only harm your body when there are too many of them.

What causes too many free radicals?

Your body is always creating free radicals during chemical processes and balancing them out with antioxidants.

But pollution, processed foods, prolonged stress and burnout, and unhealthy lifestyle choices may cause your body to create more free radicals than necessary. Not eating enough healthy foods with antioxidants can also cause an imbalance with too many free radicals.

Here is a list of some of the things that cause your body to make free radicals:

  • Inflammation
  • Radiation
  • High blood sugar
  • Infections in the body
  • Too much or too little oxygen
  • Heavy metals, such as iron, magnesium and copper
  • Too much or sudden bursts of hard exercise
  • Ischemia / reperfusion injury
  • Cigarette smoke
  • Drinking too much alcohol
  • Air and water pollution
  • Radiation
  • Certain drugs and pesticides
  • Industrial solvents
  • High temperatures
  • UV light
  • Eating a lot of polyunsaturated acids
  • Taking too many antioxidants e.g. vitamin C

What happens when there are too many free radicals in the body?

Free radicals help us with the beneficial tasks listed above, like turning oxygen and food into energy and fighting disease.

Antioxidants give electrons to free radicals to stabilize them. This is a natural process to achieve balance in the body.

But when you have too many free radicals and not enough antioxidants to balance them out, the free radicals can become destructive as they scavenge the body looking for electrons to steal.

These free radicals can damage your DNA, protein and other cells in the body. This damage is called ‘oxidative stress’ and it can make us sick.

What are the symptoms of oxidative stress?

There aren’t any official symptoms for oxidative stress, but naturopaths believe that the following are signs to look out for:

  • Fatigue and burn out
  • Being prone to infections
  • Foggy brain (often helped by a low card high fat diet)
  • Memory loss
  • Muscle and/or joint pain
  • Getting headaches often
  • Eye sight getting bad
  • Sensitivity to noise
  • Premature wrinkles
  • Premature gray hair

What diseases does oxidative stress cause?

Oxidative stress can start many diseases in the body, such as:

  • Cancer
  • Neurodegenerative diseases (in the brain) e.g. Parkinson’s, Alzheimer’s
  • Ulcers and inflammatory diseases e.g. arthritis
  • Diabetes mellitus
  • Liver damage
  • Asthma
  • Emphysema
  • Cataracts and other macular diseases in the eyes
  • Cardiovascular diseases e.g. hypertension

There is also the ‘radical theory of aging’, which states that oxidative stress makes us age. This theory believes that free radicals damage our DNA, which causes new cells not to develop properly as we age.

Where do antioxidants come from?

Your body makes antioxidants, but not enough for what you need.

The good news is that plants and animals have their own antioxidants, just like you. So, when you eat plants and healthy protein sources, you get antioxidants from these natural whole foods. I’ve found that the best way to feel better and eat better is to follow a keto or primal diet.

Studies show that eating foods high in antioxidants have much greater benefits than taking antioxidant pills or supplements.

Many foods and drinks that are high in antioxidants have other health benefits too, such as being anti-inflammatory for the body.

Foods that are high in antioxidants

Here’s a list of foods that will provide you with natural antioxidants:

  • Pineapples
  • Citrus fruits
  • Responsibly sourced, raw honey
  • Berries
  • Grass fed / free range meats and organs, especially liver
  • Wild fish / seafood
  • Dark chocolate (70%+ cocoa)
  • Nuts
  • Avocados
  • Tomatoes
  • Garlic
  • Onions
  • Kale and dark green leafy vegetables
  • Turmeric
  • Extra virgin olive oil

Drinks that are high in antioxidants

Here’s a list of drinks that are a wonderful source of antioxidants:

  • Coffee is the greatest source of antioxidants in the Western diet
  • Green tea
  • Red wine
  • Kombucha, especially when made from green tea

Are more antioxidants always better?

While antioxidants play an amazing role in keeping us younger and healthy, they need to be kept in balance with free radicals.

Taking antioxidant supplements does not necessarily improve our health, unless we are lacking that vitamin or mineral and we know we are not getting enough of it in our diet.

It’s best to consult with a professional about supplementation and to focus on eating a healthy diet.

Based on my research, there is very little proof that taking antioxidant supplements offers many, if any, health benefits. In fact, some studies reveal that taking supplements may cause diseases or be linked to early death.

Research studies and results on antioxidant supplements

Here are just some of the findings from clinical studies with antioxidants:

Too many antioxidants could cause cancer. A clinical trial in 1996 was stopped when male smokers taking beta carotene supplements had a significant increase in lung cancer rates. In another trial, women taking vitamins C and E, beta carotene, zinc and selenium saw higher rates of skin cancer.

Vitamin E supplements have only had a moderate effect in studies against heart disease.

A six-year clinical trial reported that those who were at high risk of developing age-related eye disease got some protection by taking vitamins C and E, beta carotene and zinc. But they weren’t protected against cataracts.

One study showed that taking beta carotene for longer than 15 years may give some mental health benefits. Another study reported that taking vitamin E and selenium offered no added protection against dementia.

Another study reviewed 78 randomized people taking antioxidant supplements. Both healthy people and people with established illnesses taking beta carotene and vitamin E supplements had a higher death rate than those not taking them.

Studies were carried out on over 100 000 people to see if antioxidant supplements prevented chronic diseases, such as cancer and cataracts. In most instances, these supplements had no effect on the risk of developing such diseases.

FAQs about free radicals

What are free radicals and what do they do to your body?

Free radicals are atoms with unpaired electrons. They help turn food and air into energy. They also kill off germs to protect us. But too many free radicals and too few antioxidants can cause disease.

What causes free radicals in the body?

Oxidation, a natural chemical in the body, creates free radicals. This is healthy if they are balanced with antioxidants. But pollution, an unhealthy lifestyle, hectic cardio and not eating enough antioxidants can cause too many free radicals in the body.

How do free radicals cause cancer?

Free radicals are part of a healthy body. But too many free radicals and not enough antioxidants could cause cancer when the free radicals scavenge the body looking for electrons and damage healthy cells along the way.

Are Free Radicals a real thing?

Yes, free radicals are a real thing. They are atoms in the body that have unpaired electrons and they get these electrons from antioxidants or steal them from other molecules.

Get the antioxidant grocery list

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Free radicals are extremely important in turning oxygen and food into energy. They also fight disease in the body.

Free radicals need to be balanced with antioxidants from natural, whole food sources such as raw honey, pineapple and coffee.

Taking antioxidant supplements has no marked improvement on health or disease prevention. In fact, taking such supplements may cause cancer, interact with other medicines, or have negative effects on one’s long-term health.