Free Radicals

  • Introduction
  • Reducing free radicals and free radical damage
  • References


A free radical can be defined as any molecular species capable of independent existence that contains an unpaired electron in an atomic orbital. The presence of an unpaired electron results in certain common properties that are shared by most radicals. Many radicals are unstable and highly reactive¹.”

The cells in our bodies depend on oxygen to perform various functions. When our cells react with oxygen in a process known as oxidation, free radicals are released into the body. In varying degrees, the body is continually subjected to a condition called oxidative stress.

Since free radicals are highly reactive, they have the ability to bind to and subsequently cause harm to your cells.

In practical terms, this means that free radicals can potentially add to increased risk or worsening of various medical conditions, including inflammatory and cardiovascular diseases and even cancer. They can also contribute to premature signs of ageing, such as wrinkles, age spots and loss of firmness in the skin.

So, a free radical is any atom or molecule that is missing an electron from its outer shell, making it unstable. Free radicals float around until they stabilise and they do this by attacking another molecule and stealing an electron. The molecule that has been attacked by a free radical is now missing an electron and has become another free radical creating a chain reaction.

This natural response is intensified by the secondary injury or biochemical cascade that happens immediately after the initial/primary brain injury as part of the inflammatory response to medical insult. Oxidative stress begins when oxygen in the body splits into single atoms with unpaired electrons (as above). Electrons are usually in pairs, so these atoms, called free radicals, search out other electrons so they can become a pair. It is this process that causes damage to cells.

Once free radicals are formed, a chain reaction can occur. The first free radical grabs an electron from a molecule, weakening that molecule and turning it into a free radical. That molecule then takes an electron from another molecule creating an ongoing domino effect until the whole cell suffers damage.

This chain reaction may lead to vulnerability in the cell membrane, which can change what enters and exits the cell and may change the structure of a lipid, making it more likely to become trapped in an artery. These damaged molecules can mutate and grow into tumours or change DNA code. Knowing this makes us realise how important it is to look after our bodies.

We know the inflammatory response to stress and/or brain injury/trauma can also cause a chain reaction. Part of this is oxidative stress, which again causes an increase in free radicals.

As above, damaged cells trigger the onset of other medical problems and some diseases like cancer. They also contribute to ageing because of a gradual accumulation of damage. The early appearance of wrinkles and grey hair and hair loss are one indication of free-radical damage and is often seen in people who drink, smoke and use drugs. Fried foods, chemicals, pesticides and air pollutants are also contributory to early ageing processes. It is essential to reduce oxidative stress and toxins following a brain injury.

As a natural by-product of chemical processes, such as metabolism, free radicals are also essential to life. Their ability to turn air and food into chemical energy depends on a chain reaction of free radicals. They are also a crucial part of the immune system, as they travel throughout the body attacking foreign invaders. It is when they amass, such as after a brain injury or when we abuse our bodies, that they harm our cells.

According to Dr Doni and other naturopathic practitioners, oxidative stress can cause sensitivity to noise, vision problems and lowered immunity.

While it is impossible to avoid free radicals, it is possible to reduce their concentration in the body by increasing antioxidants. Antioxidants can add an electron to a free radical without becoming destabilised themselves, which stops the free radical chain reaction. Antioxidants are plentiful in fruits and vegetables, especially colourful ones, so it is vital to make sure you focus on the quality of nutrition in your diet and stop eating ’empty calories.’

Reducing free radicals and free radical damage

Oxidative stress is defined as an imbalance between free radical production and endogen antioxidant systems. To avoid the onset of disease, we all need to take responsibility for our health and to be mindful of how our bodies work and what they need at a cellular level. As in the micro is as is in the macro and our health and longevity depend on our awareness of this.

Making conscious choices about our health, our future, and owning the responsibility for what happens to us, can make all the difference in reducing the risk of disease onset that we can’t control.

Science tells us that brain injury increases the risk of many inflammatory-related and trauma-induced diseases.  If we respond and take ownership of our health, we can make a difference. Don’t just browse helpful advice when you come across it – act on it.

Besides improving the quality of your nutritional intake, there are also other ways to start reducing free radical damage:

  • Stop smoking
  • Do not use ‘recreational drugs
  • Reduce alcohol
  • Eliminate sugar, mined salt and processed foods
  • Check the purity of your water
  • Avoid environmental pollutants
  • Reduce your chemical exposure in household and cosmetic products
  • Review your medications with your doctor
  • Reduce stress in your life and ask others to help with this
  • Try to take moderate amounts of exercise on a regular basis
  • Get out in the fresh air and daylight every day
  • Consider starting the One, Two, Three Plan


(1) NCBI – Free radicals, antioxidants and functional foods: Impact on human health

ResearchGate – Traumatic Brain Injury: Oxidative Stress and Neuroprotection