Free Radicals & Antioxidants

free radical and antioxidant

A Free Radical is a molecule with an unpaired electron. It is highly unstable because of this & roams around in the circulation, stealing electrons from healthy cells, thereby destroying those cells.

Free radicals are implicated in diseases such as arthritis, atherosclerosis, Parkinson’s, cancer and Aids but what exactly is a free radical?

Where do they come from?

Free radicals originate from our environment. Radiation, air pollution, aerosols, paints and other fumes generate free radical production. A major source of free radicals is from foods containing additives such as artificial colours, flavours, preservatives, herbicides and pesticides. Drugs, chemotherapy, paracetamol etc also cause damage by free radical formation. Some natural body processes produce free radicals. Examples are exercise, energy production by the mitochondria-the powerhouse of the cell, infection, operation and illnesses. The immune system also relies on free radicals to keep harmful microorganisms under check. Free radicals are necessary and yet potentially harmful.

Effects of free radicals on the cell membranes

Cells make up our body. The cell membrane is the outside of the cell. A healthy cell membrane is required to enable communication between cells and maintain healthy cells. Free radicals damage membrane proteins therefore alter cell identity and can cause an autoimmune response as the body does not recognise them and tries to destroy them. They also cause the cell membrane to harden as they damage proteins and fats in the membrane, which subsequently fuse together, thereby decreasing the permeability of the cell. They can actually ruptures the cell membrane also, leading to death of the cell. Another area that is affected by free radicals is the DNA. Our DNA may become mutated or destroyed to an extent that cells / tissues and organs cease to function effectively.

Examples of free radical damage

Free radical damage is implicated in all diseases. Common examples are the following;


Free radicals circulate within the fluid of the joints. This damages the synovial lining, allowing synovial fluid to leak out, resulting in decreased shock absorption.


Free radicals attack the lipoproteins, HDL the good cholesterol, and LDL the bad cholesterol. Damage to LDL results in increased cholesterol in the blood. Free radicals also circulate within the circulatory system. They attack the epithelial lining of the arteries and veins, resulting in scratches on the walls. Fat can then deposit into these scratches. This is the process for the build up of atherosclerotic plaques. Evidence of these scratches is present in 50% of children aged 10-14,who have a diet high in junk food.


Free radicals damages membrane proteins, therefore alters cell identity and can cause an autoimmune response. Prolonged periods of autoimmune dysfunction can result in the immune system to not being able to recognise foreign products or antigens, in this case cancerous cells. This can lead to uncontrolled division and growth of blood cells, which is the nature of cancer.


Free radicals damage helper T lymphocytes. HIV drugs produce more free radicals further perpetuating the disease.


Free radicals cause cellular damage to tissues and organs, leading to hypofunction and eventually cell death. Wrinkling is caused by free radical damage to connective tissue. Age spots are pigments damaged by free radicals.

What exactly are antioxidants?

We know they’re in tea, tomatoes, chocolate and red wine, but what are they and what do they do? Antioxidants neutralise free radicals by supplying the electron or taking away the unstable electron to stabilise the molecule. This halts the initiation of a chain of negative events. Anti-oxidants can be enzymes, amino acids/proteins, vitamins and trace elements.

free radical and antioxidant

Antioxidant nutrients

Beta-carotene or vitamin A - is especially important for protection of skin, lungs, reproductive system and eyes.Beta-carotene-vitamin A Inhibits singlet oxygen (very reactive) and is of primary importance to neutralise free radicals in the eyes, especially important to prevent macular degeneration. Please note that vitamin A enhances epithelial growth in tissues and is not an anti-oxidant per say.

Ascorbic acid-vitamin C Neutralises free radicals and is of particular importance to protect connective tissue. Ascorbic acid or vitamin C enhances collagen synthesis.

Alpha tocopherol / vitamin E - Stabilises and protects the phospholipid bilayer in cell membranes. This nutrient should be professionally prescribed and is contraindicated in anti-coagulant users. i.e. warfarin or aspirin. Selenium Important component of glutathione peroxidase the most commonly used pathway in phase II detoxification in the liver.

Alpha tocopherol or vitamin E and selenium are potent free radical scavengers - Selenium protects all membranes from lipid peroxidation, neutralises hydrogen peroxide, protects vitamin E, slows the biochemical aging process, protects against cardiovascular disease and enhances the effects of vitamin E thereby increasing antibody formation by 20-30 times.

Other nutrients  - There are many products on the market that are potent antioxidants. The following are good examples; sulphur containing amino acids such as cysteine and methionine, grape seed extract, muritino pine extract, bilberry, milk thistle and chaparral.

For further details on this topic, to lecture for your group or institution on this subject. or to arrange an online appointment contact Carina This email address is being protected from spambots. You need JavaScript enabled to view it..

Carina Harkin BHSc.Nat.BHSc.Hom.BHSc.Acu.

Cert IV TAE. 

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