Free Radicals I

Our body is made up of cells. Every cell is made up of molecules and the molecules in turn are made up of atoms. Therefore our body is made up of atoms. Atoms have a nucleus consisting of protons and neutrons. Nucleus is surrounded by electrons, a negatively charged particles. An atom becomes a radical when it loses an electron or a radical is a charged atom. Radicals may be positively, negatively or zero charged.

Radicals are atoms or group of atoms or ions with the unpaired electron in the outermost orbit. They are charged atoms and are highly reactive. The unpaired electrons in the outermost orbit make them highly reactive. All the elements are capable of producing radicals as they are ready to lose the electrons from the outermost orbit. But we are concerned with only oxygen radicals because we are living in the atmosphere of oxygen.

The chemical behaviour of an atom is determined by the number of electrons in the outermost shell. When the outermost orbit is completely filled with eight electrons, the atom is stable and does not take part in any chemical reaction. When the outermost shell is not full, the atom is unstable.  It will try to stabilise by either sharing the electron pair or by losing or gaining the electron pair.   

An oxygen atom has a total number of eight electrons. Two electrons will occupy the first orbit. The remaining six electrons will occupy the second or the outermost orbit. Out of the six electrons, four electrons are paired. Two electrons are unpaired.  Oxygen atom loses the unpaired electron to become a free radical. Now oxygen radical will try to steal the extra electron from the neighboring oxygen atom to stabilize. The neighboring oxygen atom becomes a free radical and will try to stabilize by stealing an electron from its neighboring oxygen atom. This leads to a chain of free radicals formation.

A free radical is an atom or a group of atoms that has an unpaired electron and is therefore unstable and is highly reactive. This enormous chain of free radicals will create a havoc on living tissues. It is estimated that the chain reaction can trigger 6.023 x 1021 billion molecules to react per second!

We live in a world surrounded by free radicals. Free radicals are unstable oxygen molecules with missing electrons. Free radicals are beneficial in small quantities to destroy pathogens, parasites, bacteria and virus that invade our body. But excess free radicals are the greatest threat to our health.

Free radicals are found everywhere. They are found in sunlight, the food that we eat, the air that we breathe and the water that we drink. So our body absorbs free radicals  from all the above elements. Environmental factors also contribute to excess of free radicals in our body.

In addition, cigarette smoking, drinking alcohol, pollution of all types, frequent exposure to X-rays, eating microwaved food and processed food and junk food cause excess free radical production  in our body.  Since free radicals can cause chain reaction, the cells of our body are damaged and it becomes a great threat to our health and wellbeing. It is proved that all the cells of our body come under attack nearly 10000 times in a day by free radicals. So free radicals are the natural part of our life system.

Free radicals are molecules, usually of oxygen, that have lost an electron. That loss makes them unstable and reactive. They attain stability by stealing the neighbouring molecules' electrons. In stealing an electron, they operate as terrorists in our body. They can attack DNA, leading to dysfunction, mutation, and cancer. They can attack enzymes and proteins, disrupting normal cell activities, or cell membranes. Such membrane damage in the cells that line our blood vessels can lead to hardening and thickening of the arteries and eventually to heart attacks and strokes. Free-radical attacks on collagen can cause cross-linking of protein molecules, resulting in stiffness in the tissue.

The constant attack of oxygen radicals on our body is called oxidative stress which manifests as diseases like cancer, atherosclerosis, heart diseases, cerebrovascular diseases, stroke, emphysema, diabetes, osteoporosis, arthritis, ulcers, cataract, ageing, senility and so on.

Production of free radicals in our body is continuous.  The basic causes are:

The cells of the immune system creates highly reactive oxygen radicals. The other dangerous and molecular variety is Reactive Oxygen Species (ROS). These are not free radicals but they less unstable but highly reactive.  ROS radicals are weapons.

In every cell, energy is being produced for various metabolic activities. Therefore the cells produce free radicals.

Our body produces free radicals when we are stressed. Hormones produced by the body when it is stressed produce free radicals in abundance.  When we lead a stressful life our body produces more free radicals and we suffer from variety of illnesses like fatigue, forgetfulness, elevated BP and sugar.

Pollutants generate free radicals in our body. The food that we eat contain hidden chemicals as our food is grown using pesticides, chemical fertilizers etc. When we ingest the food our body produces free radicals. So it is necessary that our food should be grown using organic methods.

Children are fond of processed foods. Adults are also used to eating processed foods and fast foods. They contain high levels of lipids which produce free radicals that damage the cardiovascular system.

Cigarette smoke generates free-radical concentrations. Lung damage is associated with smoking and is caused by free radicals.  Air pollution has similar effects. Alcohol is a potent generator of free radicals. So do not smoke cigarettes and do not drink alcoholic beverages.  

When we eat deeply fried foods, free radicals are produced in our body.

In addition, free radicals can result from sun-light. Exposure to sunlight generates free radicals that age the skin, causing roughness and wrinkles. If the exposure is prolonged, free radicals generated from sunlight causes skin cancer.

(To be continued)