Free radicals were little known to most of us 25 years ago. Researchers are beginning to uncover the damage throughout the body that excess free radicals can cause.  To begin understanding free radicals, one must understand basic chemistry.

Your cells are made up of atoms. These atoms are the fundamental building blocks of everything. Atoms can join together to form molecules.

As you may or may not remember from high school, atoms consist of a nucleus, neutrons, protons and electrons. The number of protons (+ charged) in the atom’s nucleus determines the number of electrons (- charged) surrounding the atom. Atoms want to be balanced and stable. These electrons are involved in chemical reactions and are what holds multiple molecules together.

As I previously mentioned atoms want to be stable. They achieve this by filling their outer shells with electrons. For example, at the center of an atom is a nucleus, which holds protons and neutrons. Outside of this is an inner shell that holds two electrons, once filled electrons fill the outer shell until it reaches capacity (8 electrons). When an atom is complete it does not enter in chemical reactions and is considered stable. Because atoms seek a state of stability, an atom will try and fill its outer shell, either by gaining or losing electrons or by sharing electrons with other atoms.

When an atom or group of atoms has at least one unpaired electron, it is considered unstable and highly reactive. These are called free radicals. Free radicals are unstable and will attack other atoms, stealing their electrons. When this occurs the result is another free radical, beginning a chain reaction. The process can result in the disruption of living cells.

How are free radicals formed?

Some free radicals arise during normal functions such as metabolism. There are tens of thousands of free radicals formed in the body every second.  The immune system creates free radicals to neutralize viruses and bacteria. Environmental factors such as pollution, radiation and cigarettes can create free radicals as well. This can cause excessive free radicals that overwhelm the body’s ability to handle them. This imbalance can result in oxidative stress. Oxidative stress is damage to the function and structure of a cell by overly reactive oxygen-containing molecules.

While we think of oxygen as vital to life, it is also responsible for the destruction and aging of all living things.

Some examples of Oxidative Stress are:

oxidative stress in fruitThe skin of fruit provides a barrier against oxidation. This is why fruit looks healthy and delicious at the grocery store but after 7-10 days oxidation breaks down the barrier exposing the individual cells to the air (oxygen molecules). The result is brownish spots and bruising. This is a form of rust. Or how about this apple, the moment the soft inside is exposed to air it begins to brown and oxidize.
oxidative stress on a carAutomobiles- A major problem for car owners is oxidation. If a car’s outer finish is not coated properly, the paint interacts with oxygen molecules damaging the paint. Restoration efforts can be time consuming and expensive therefore professional car detailers recommend at least one layer of wax or protectant every time a car is washed.

If oxidative stress is fast enough to age fruit within moments of exposure and strong enough to eat away at metals and paint, imagine the damage it can inflict on your body. How can you neutralize oxidative stress?

Different Types of Free Radicals

There are six different types of free radicals:

Superoxide Radicals (O2)
Our bodies continuously form these as part of cellular energy production and immune response, but they also come from environmental factors including car exhaust and cigarette smoke. 02 can be converted by iron or copper to the more toxic OH.
Hydroxl Radicals (OH)
Also known as hydrogen peroxide, these are the most aggressive and damaging radicals known. These free radicals interact with anything it touches. These are formed in the body as part of normal metabolism and are particularly harmful to cellular membranes. Approximately 5 to 10% of the oxygen we breathe is converted to OH.
Nitrous Oxide (NO)
Nitrous oxide reacts with oxygen to form the more damaging oxident, nitrogen dioxide (NO2)
Nitrogen Dioxide
Nitrogen dioxide is formed in the body when NO reacts with an oxygen molecule however it is also a component of pollution. NO2 is a major concern to those with lung problems and is found in high concentrations among asthmatics.
Ozone (O3)
An air pollutant which damages the lungs and other vital tissues.
Single Oxygen Molecule (O)
Singlet oxygen is produced in the body through various chemical reactions.


An antioxidant is a molecule that inhibits these dangerous molecules. Substances in our diet (namely, vitamin C and vitamin E) neutralize free radicals by donating an electron to stabilize the molecule. Antioxidant molecules do not become free radicals therefore once it has found a free radical and neutralized it, the chain has stopped.

Getting sufficient antioxidants are essential in reducing oxidative stress therefore a proper diet and/or supplementation is necessary to boost levels of vitamin C and E in your body.Controlling the ratio of oxidants to antioxidants is vital to your overall health.

Read more about Antioxidants.