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Quest Vitamins LTD,
8 Venture Way,
Aston Science Park,
B7 4AP.

Tel: 0121 359 0056
Fax: 0121 359 0313
Registered in England No. 2530437

Immune System


The immune system may be described as an army waging an ongoing war against potential invaders such as bacteria, viruses and fungi. Many of us do not appreciate its complexity, but our immune system is a highly organised network of specialised cells with the ability to selectively destroy disease-causing microorganisms. Organs of the immune system include the liver, spleen, thymus and Lymphatic System.


The job of the immune system is to recognise and dispose of foreign or non-self particles. This is vital for keeping our bodies free of disease and Infection, but the efficiency of the immune system can sometimes cause problems. For instance, transplant surgeons have to overcome the problem of rejection or else life saving organs are destroyed by the body. In addition, the immune system is sometimes a little over-zealous, mounting an immune response to harmless substances such as pollen or dust.

The Skin is the first line of defence against invading pathogens but if this is breached then the white blood cells - the body?s "infantry" against disease - spring into action. White blood cells are manufactured in the bone marrow but mature elsewhere in the body. There are three main classes:

Phagocytes - a type of immune cell that engulfs foreign particles.

B-lymphocytes - these cells produce antibodies (proteins which tag foreign particles so that they can be destroyed by phagocytes).

T-lymphocytes - destroy virus invaded cells and mutant cells by non-phagocytic means.

The most remarkable feature of the immune system is its ability to remember past encounters with foreign particles or microorganisms, such that if it is confronted with them again, it has a certain amount of resistance and can mount a swift response. Throughout our lives the immune system is continually evolving, building up resistance to a variety of different strains of bacteria, viruses etc.

The immune system of a new born baby is very immature and is unable to synthesise antibodies, leaving the baby at the mercy of a number of pathogens at such a vulnerable time. Fortunately, antibodies transfer from the mother to the foetus during Pregnancy, thereby providing a small amount of protection. In addition, the mother?s breast milk contains valuable antibodies, which provide further protection against disease.


The immune system is not perfect and its efficiency can be affected by a number of factors including:

Nutritional Status
Using certain types of drugs
Alcohol intake
Fatigue and Stress

Whilst there is nothing we can do about our gender, ethnic origin or genetic make-up, we can take control of other aspects of our lives to ensure that the immune system does not become compromised in any way. Safeguarding intakes of essential nutrients for immune function such as vitamins A, C and E, Selenium and Zinc, and limiting alcohol consumption are just two steps that can go a long way to maintaining the strength of the immune system.


Conditions affecting the functioning of the immune system can be divided into three classes:

Immune deficiency diseases

Autoimmune diseases
The immune system is not perfect and its ability to distinguish between self and non-self may become defective and an autoimmune disease may result. Classic examples of autoimmune diseases are rheumatoid Arthritis and Multiple sclerosis.

Rheumatoid arthritis
Rheumatoid Arthritis is caused by the body?s immune system attacking the joints, resulting in Inflammation and causing severe Pain to the sufferer. The disease affects one to two per cent of the population and is more common in women than men (1).

Treatment for the disease varies from person to person but usually involves the use of non-steroidal anti-inflammatory drugs to relieve joint pain and stiffness. In some cases, immunosuppressant drugs are used to slow the progression of the disease, but this treatment may also be accompanied by unwanted side effects. Consequently, many sufferers supplement with Evening Primrose Oil, a rich source of the omega-6 fatty acid, gamma linolenic acid (GLA). GLA is converted by the body into beneficial prostaglandins which may help to correct a faulty immune system (2).

Multiple Sclerosis
Multiple sclerosis (MS) is a disease of the central nervous system where the sheaths surrounding the nerves (myelin) are gradually destroyed. This leads to symptoms ranging from numbness and tingling to paralysis. The cause of the disease is unknown but it is thought that the destruction of the myelin is caused by the body?s immune system not recognising the myelin as ?self?. There seems to be a genetic predisposition to the disease and relatives of an affected person are eight times more likely to develop the disease. In addition, the environment seems to affect the chances of developing the disease, with people living in Europe and the US five times more likely to develop the disease. It is suspected that a virus endemic in temperate parts of the world initiates the condition (1). However, further research is still required. Many people with MS supplement with Essential Fatty Acids together with vitamin B6 and B12 to slow the progression of the disease as these nutrients are required for the health of the nerves.

An efficient immune system is vital for keeping us healthy and free of disease. However, inappropriate or excessive stimulation can cause problems, such as allergies. An Allergy is an immune response to a harmless substance such as dust or pollen. Exposure to these substances (or allergens) may cause annoying symptoms such as itchy Eyes, sneezing and a runny nose. In some cases, such as with a peanut allergy, the immune response can be so severe that it is life-threatening. There are two main types of allergy: immediate hypersensitivity where symptoms are expressed within 20 minutes and delayed hypersensitivity where the onset of symptoms occurs within 1-3 days of exposure to the allergen.

Hay Fever is a good example of an immediate hypersensitivity reaction where certain inhaled substances (frequently pollens) stimulate the production of antibodies. These antibodies bind to mast cells which release histamine resulting in the local dilation of blood vessels. Histamine production in the upper respiratory tract results in sneezing and a runny nose (due to increased mucous secretion - a result of localised irritation).

There is no cure for hay fever but avoiding the allergen which provokes the immune response is the best way of avoiding the misery associated with the condition. Alternatively, Echinacea may help to support the health of the immune system (3,4) and when combined with Vitamin C (a natural antihistamine) (5) the benefits are further increased.

Immunodeficiency diseases
An immune deficiency disease may be congenital (present at birth) or acquired. A good example of a congenital immune deficiency disease is severe combined immunodeficiency. This disease is a rare hereditary condition characterised by the absence of both the B and T cells. Sufferers of the disease are unable to fight disease-causing bugs and usually die at an early age unless kept in a sterile environment.

Alternatively, an immune deficiency disease may be acquired. Reasons for this include cancer treatment, the use of anti-inflammatory agents such as cortisol derivatives and Infection with HIV, which usually leads to acquired immune deficiency disease (AIDS).


Subtle changes to the diet and the use of nutritional supplements can be very useful for supporting immune health. The efficiency of the immune system may be compromised by a diet high in saturated fat or cholesterol. Research has shown that subjects consuming a diet rich in cholesterol have a diminished immune response.

Scientists have yet to establish a definitive link between caffeine intake and impaired immunity, but it may be wise to limit consumption of caffeinated drinks such as tea, coffee and coke. Vitamin C is fundamental to immune health and research has shown that during an Infection, levels of this nutrient may become depleted (6). As a result, many people choose to supplement with 1-2g vitamin C per day. Also, a regular intake of at least 1000mg Vitamin C may help to reduce the duration of the Common Cold and the severity of symptoms (7).

Vitamin A is required for maintaining the health of mucous membranes and increased intakes may be useful for warding off respiratory Infections. Additionally, supplementing with 400i.u. Vitamin E may help to support a healthy immune response.

Zinc is an essential mineral for immune function and a minor deficiency can have serious effects on all aspects of the immune system. Those troubled with frequent Infections or people who eat little or no meat, fish, cheese, eggs, pulses and seeds (rich sources of zinc) may wish to take a zinc supplement.

Aged garlic extract possesses potent anti-viral, anti-bacterial and anti-fungal activity and scientific studies have shown that it stimulates various facets of the immune system. It is particularly useful during the winter when colds and flu are more prevalent.

Echinacea purpurea is a herb which is used traditionally as an immune stimulant. The herb contains useful compounds which stimulate the production of white blood cells, thereby helping to reduce the body?s susceptibility to Infection (8).


Evening Primrose Oil
Aged Garlic extract


Vitamin A
Vitamin B6
Vitamin B12
Vitamin C
Vitamin E


1. The BMA Complete Family Health Encyclopedia, Ed. Dr T Smith. 1995.
2. Prog. Lipid Res, 1992, 31;2:163-194.
3. Arzneim Forsch, 1985, 35:1069-1075.
4. Arzneim Forsch, 1985, 35: 1437-1439.
5. In vivo, 1994, 8;2:251-7.
6. Ann Nutr Metab, 1997, 41;6:344-352.
7. Br J Nutr, 1997, 77; 1:59-72.
8. Herbal Medicines: A Guide for Healthcare Professionals, C A Newall, LA Anderson, J D Phillipson, The Pharmaceutical Press, 1996.

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