What are free radicals? - Nature Cures®

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The human body is composed of many different types of cells that, in turn, are composed of many different types of molecules. The following is an explanation of how free radicals are formed.

Molecules consist of one or more atoms of one or more element joined by chemical bonds.

The number of protons (positively charged particles) in the atom’s nucleus determines the number of electrons (negatively charged particles) surrounding the atom.

Atoms have layers (or shells) of pairs of electrons.

Electrons orbit an atom in one or more shells (layers). The innermost shell is full when it has two electrons.

When the first shell is full, electrons begin to fill the second shell. When the second shell has eight electrons it is full and so on.

Electrons are involved in chemical reactions and are the substance that bonds atoms together to form molecules.

Generally, chemical reactions are interactions between the electrons of the outermost shell between two atoms.

Because electrons in atoms generally exist in pairs, the negative charge causes them to repel each other, but electrons spin (orbit) around the atom creating a magnetic pull. Since they spin in opposite directions, each electron of a pair of electrons has opposite magnetic pulls (like north and south) which holds two electrons of a pair near each other.

The structural feature of an atom that determines its chemical behaviour is the number of electrons in its outer shell.

A substance that has a full outer shell tends not to enter into any chemical reactions (an inert substance). Because atoms seek to reach a state of maximum stability, an atom will try to fill its outer shell by gaining or losing electrons to either fill or empty its outer shell or sharing its electrons by bonding together with other atoms in order to complete its outer shell.

Atoms often complete their outer shells by sharing electrons with other atoms. By sharing electrons, the atoms are bound together and satisfy the conditions of maximum stability for the molecule. When it is difficult to take an electron from an atom, that molecule is known as being stable.

Noble gases argon, helium, krypton, neon, radon and xenon are the chemical elements in group 18 of the periodic table. They are the most stable due to having the maximum number of electrons their outer shell can hold. Therefore, they rarely react with other elements since they are already stable.

Ions are electrically charged particles formed when atoms lose or gain electrons. They have the same electronic structures as noble gases. Metal atoms form positive ions, while non-metal atoms form negative ions. The strong electrostatic forces of attraction between oppositely charged ions are called ionic bonds.

How are free radicals formed?

An atom can lose an electron from its shell, leaving the atom with an unpaired electron (a free electron).

The spin of the free electron has a magnetic pull that is no longer countered by an electron spinning in the opposite direction.

The magnetic pull of the free electron, and other forces due to the loss of its partner electron, cause the free electron to easily pair up with (react with) an electron of a pair of another atom, causing the two atoms to be held together by the paired-up electrons.

The new pair of electrons holding the two atoms together is the bond between the two atoms (covalent bond). The electron pushed out becomes a new free electron.

The new free electron pairs up with an electron of another atom, pushing out one of the electrons in the process, again creating a new free electron.

The displacing and replacing of electrons continue through hundreds and even thousands of atoms until finally two atoms with a free electron (spinning in opposite directions) pair up forming a bond between the two atoms.

Normally, bonds do not split in a way that leaves a molecule with an unpaired electron. But when weak bonds split, free radicals are formed. Simply put atoms that have a singular free electron are called free radicals.

Free radicals are very unstable and react quickly with other compounds, trying to capture the needed electron to gain stability.

They will attack the nearest stable molecule and steal its electron. When the attacked molecule loses its electron, it becomes a free radical itself, beginning a chain reaction, as it too will then attack and steal an electron from a nearby molecule.

Once the process is started, it can cascade, like a domino effect, finally resulting in the disruption of a living cell. Thousands of free radical reactions can occur within a few seconds of the primary reaction.

Are all free radicals damaging?

In the human body free radicals can be useful because they help important reactions to take place. Free radicals arise normally during metabolism and sometimes the immune system’s white blood cells purposefully create them to neutralise bacteria and viruses.

Free radicals are a natural by-product of the body when it turns food into energy and, normally, the body makes its own antioxidant enzymes to deal with them. Catalase, glutathione peroxidase and superoxide dismutase are three such enzymes and they require micronutrient cofactors such as copper, iron, manganese, selenium and zinc for their activity.

Excess free radicals are a problem because they attack the body itself, damaging key cellular molecules such as DNA. Cells with damaged DNA are more prone to developing cancer and free radical damage accumulates with age.

Possible results of free radical damage

Arthritis
Adrenal fatigue
Alzheimer’s disease
Attention deficit hyperactivity disorder (ADHD)
Atherosclerosis
Autism
Bi-polar disorder
Cancer
Cataract formation
Chronic fatigue syndrome
Crohn’s disease
Depression
Diabetes
Fibromyalgia
Heart disease
Huntington’s disease
Hypertension
Hyperthyroidism
Inflammation and pain
Bladder and kidney stones
Macular degeneration
Methylenetetrahydrofolate reductase (MTHFR) gene mutations
Multiple sclerosis
Parkinson’s disease
Premature ageing
Rheumatoid arthritis
Stroke
Tinnitus

The root cause of a number of degenerative diseases, related to free radicals, is that free radicals take electrons from the atoms of lipids more easily and more frequently than other molecules. In diabetes the cause is widely believed to be the free radical damage of the lipids of the cell membrane (cell wall) adversely affecting the membrane in a way that prevents the membrane from detecting or responding to insulin molecules.

Free radical damage of lipids is also believed to be the culprit in Alzheimer’s disease and other brain degeneration conditions. Free radical damage may stem from heavy metals in the brain

Heavy metals and free radicals

When a free radical collides with a heavy metal particle, instead on just one new free radical being created, the chemical reaction increases the creation of free radicals millions of times from this one impact. Then they all travel off in different directions searching for the electron to make themselves stable again.

This process damages the surrounding molecules, cell structures and DNA. It can cause premature aging, cell mutations, wrinkles and damage the immune function.

This is why it is so important to help the body cleanse itself of heavy metals and toxins. See>> Heavy metals

Sources of free radicals

A series of chemical reactions that changes molecules to different molecules is called a metabolic pathway. Metabolism of food is the numerous pathways involved in breaking food down for building blocks (spare parts) and for extracting and storing the energy from food.

Metabolism of the body includes the building of molecules from spare parts needed to keep the chemical reactions of the body going and to maintain the structures of the body.

About 98% per cent of the oxygen humans breathe combines with hydrogen and leaves the body as water (H2O) without causing problems. Around 2% of the oxygen atoms humans breathe loses an electron during metabolism, becoming a free radical. Humans breathe in around 7.2 kg or oxygen per day meaning that 0.144 kg become free radicals.

There are two sources of free radicals. Internal (endogenous) free radicals are created inside cells during metabolism of food molecules. External (exogenous) free radicals come from outside the body from the factors listed below.

Causes of excessive free radicals in the body

Alcohol
Burnt food
Charcoal cooking
Excessive exercise (normal exercise does not have this effect)
Excessive medications
Food additives
Fried food
Fungicides, herbicides and pesticides
Infections
Irradiated food
Overheated food
Ozone
Polluted environments
Radon gas
Radiation
Smoking tobacco
Stress
Sunbathing
The process of metabolism and cell respiration
Ultraviolet lights

You can see from this list that many people will be producing far too many free radicals for the normal body processes to cope with, so they need to be sure that they take in enough foods with antioxidant abilities to de-activate these excess free radicals.

Oxidative stress means an unbalance between pro-oxidants and antioxidant mechanisms. This results in excessive oxidative metabolism. This stress can be due to several environmental factors as mentioned above. Oxidative damage to DNA, proteins and other macromolecules may lead to a wide range of human diseases most notably heart disease and cancer.

Many factors can induce free radical formation in the environment. They cause clothes to fade, food to spoil, metal to rust, pipes to leak, the deterioration of plastics, the fading and peeling of paint and the degradation of works of art.

Antioxidants

An antioxidant is not actually a substance; it is a behaviour. Any compound that can donate electrons and counteract free radicals has antioxidant properties. Antioxidants prevent free radicals from oxidising (removing electrons from) sensitive biological molecules.

Cell membranes are made of unsaturated lipids. The unsaturated lipid molecules of cell membranes are particularly susceptible to this damaging free radicals process and readily contribute to the uncontrolled chain reaction. Oxidative damage, another name for the chemical reaction that free radicals cause, can lead to a breakdown or even hardening of lipids, which makeup all cell walls.

If the cell wall is hardened (lipid peroxidation) then it becomes impossible for the cell to properly get its nutrients, get signals from other cells to perform an action (such as firing of a neuron) and many other cellular activities can be affected. In addition to the cell walls, other biological molecules are also susceptible to damage, including RNA, DNA and protein enzymes.

Antioxidant supplement warning

Antioxidants derived from food sources play a vital role in keeping free radicals in check, but the latest studies call into question high levels of antioxidant supplementation. Among the most popular antioxidant supplements are vitamin C, vitamin E, beta-carotene, the pre-cursor form of vitamin A or lycopene and lutein. Taking these supplements containing high doses, instead of consuming natural foods containing these nutrients, can have the opposite effect desired and actually protect cancerous tumour cells from the body’s defences.

Antioxidants can even accelerate the growth of early tumours or precancerous lesions in high-risk people such as smokers and patients with chronic obstructive pulmonary disease who receive vitamin E and N-acetyl cysteine (NAC) to relieve mucus production.

To find out the highest natural food sources of these antioxidants see the links below.

Compounds with antioxidant abilities

The antioxidant nutrients themselves do not become free radicals by donating an electron because they are stable in either form. They act as scavengers, helping to prevent cell and tissue damage.

Vitamin C is the most abundant water-soluble antioxidant in the body and acts primarily in cellular fluid. It is especially effective at combating free-radical formation caused by pollution and cigarette smoke and also helps return vitamin E to its active form.

Nickel and vitamin C share a common antagonist, vitamin E. This inhibiting effect of vitamin E is not related to the antioxidative properties of vitamin C or vice versa (both are antioxidants, so in that respect they are synergistic), but they are antagonists ratio wise to one another, and to other chemical members:

For instance, vitamin C increases iron uptake, which Vitamin E inhibits. Vitamin C lowers manganese and zinc, while vitamin E helps increase manganese and zinc absorption. As a result, a very high intake of vitamin C will require an equally high intake of vitamin E to maintain the same ratio.

Vitamin E is the most abundant and efficient chain-breaking fat-soluble antioxidant in the body. Carotenoids and vitamin C work in synergy with vitamin E.

Highest sources of vitamin C in milligrams per 100 grams

Acerola cherries 1677.6 mg
Camu camu berries 532 mg
Rosehips 426 mg
Green chillies 242.5 mg
Guavas 228.3 mg
Yellow bell peppers 183.5 mg
Black currants 181 mg
Thyme 160.01 mg
Red chillies 143.7 mg
Drumstick pods 141 mg
Kale 120 mg
Jalapeno peppers 118.6 mg
Kiwi fruit 105.4 mg
Sun dried tomatoes 102 mg
Broccoli 89 mg
Brussel sprouts 85 mg
Cloves, saffron 81 mg
Chilli pepper 76 mg
Mustard greens 70 mg
Cress 69 mg

Persimmons fruit 66 mg
Swede 62 mg
Basil 61 mg
Papaya 60 mg
Rosemary 61 mg
Pomelo fruit 61 mg
Strawberries 58 mg
Chives 58 mg
Oranges 53.2 mg
Lemons 53 mg
Pineapple 48 mg
Cauliflower 48 mg
Kumquats 43.9 mg
Watercress 43 mg
Wasabi root 41.9 mg
Kidney bean sprouts 38.7 mg
Melon 36.7 mg
Elderberries 36 mg
Breadfruit 29 mg
Coriander 27 mg

Highest sources of vitamin E in milligrams per 100 grams

Wheat germ 149.4 mg
Hemp seeds 55 mg
Hazelnut oil 47 mg
Almond oil 39 mg
Sunflower seeds 38.3 mg
Chilli powder 38.1 mg
Paprika 38 mg
Rice bran oil 32 mg
Grape seed oil 29 mg
Almonds 26.2 mg
Oregano 18.3 mg
Hazelnuts 17 mg
Flaxseed oil 17 mg
Peanut oil 16 mg
Hazelnuts 15.3 mg
Corn oil 15 mg
Olive oil 14 mg
Soya bean oil 12 mg
Pine nuts 9.3 mg
Cloves (ground) 9 mg
Peanuts 8 mg
Celery flakes (dried) 6 mg
Spirulina 5 mg
Dried apricots 4.3 mg
Bell peppers (red), eel, olives and salmon 4 mg
Jalapeno peppers 3.6 mg
Anchovies 3.3 mg
Broccoli, chicken, chilli peppers (sun-dried), cod, crayfish, dandelion greens, egg yolk, duck, goose, pecan nuts, spinach, tomatoes (tinned or pureed) turkey and turnip greens 3 mg
Avocado, beef, bilberries, blue berries, butter, chicory greens, cinnamon (ground), crab, halibut, herring (pickled), mackerel, marjoram, mustard greens, pistachio nuts, poppy seeds, sardines, sesame seeds, Swiss chard, trout, tuna, turnips and walnuts 2 mg
Fish roe 1.9 mg
Asparagus, kiwi fruit and parsnips 1.5 mg
Black berries 1.2 mg
Chlorella 1.1 mg

Premature aging

According to the free radical theory of aging, cells continuously produce free radicals, and constant radical damage eventually kills the cell. When free radicals kill or damage enough cells in an organism it contributes to aging degeneration of the various parts of the body including the bones, brain, ears, eyes, heart, muscles, liver and skin.

A lot of the symptoms of ageing are signs of free radical damage. When cell membranes are attacked by free radicals, they either become hardened so that nutrients cannot get into the cells or they may be punctured so that the cell collapses as the cell fluid drains out.

If this happens to skin cells, it causes the skin to become leathery or wrinkled and sagging. In the joints, this causes the synovial fluid to lose its lubricating quality and cause stiffness, inflammation and pain. In cells it may damage the DNA causing cell division of cells that would normally be instructed to eliminate themselves which is what causes the tumours of cancer.

The average life expectancy may be increased by five or more years through consuming a nutritious refined sugar-free diet which includes plenty of free radical reaction inhibitors (antioxidants).

The human body naturally produces free radicals and the antioxidants to counteract their damaging effects. However, in most cases, free radicals far outnumber the naturally occurring antioxidants. In order to maintain the balance, a continual supply of external sources of antioxidants is necessary in order to obtain the maximum benefits.

Some antioxidant molecules are too big to go through the gut wall, so they work in the gut itself. Some antioxidants are water-soluble so can go where the fat-soluble ones cannot get into. Some work on the surface of cells and some work inside cells. Because different antioxidants work in different areas of the body, the key is to eat as wide a range of foods with antioxidant abilities as possible.

Astaxanthin is the most powerful antioxidant known to mankind and it gives the pink colour to sea foods such as lobster, prawns, red krill and wild salmon so these foods are important also. Red krill oil is the best provider of this antioxidant because they reside above the mercury contamination in the oceans and are too short-lived to become contaminated like many other sea creatures are.

Krill also provides vitamin D and omega-3 fatty acids which assist the body’s immune system. Take one high strength capsule of red krill oil every day.

For more information about eliminating toxins from the body see>> Cleanse and detoxify

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