The body's circulation system is usually understood to include: the heart; the blood vessels — veins, arteries and capillaries and, blood.

But there is another circulatory system in your body. It contains a clear fluid that surrounds all the cells of the entire body. It is formed when serum leaks out of the walls of the smallest blood vessels called capillaries and bathe the body tissues. This fluid is called lymph and is collected, filtered, and transported by the lymphatic vessels and channels from all areas of the body back to the blood circulatory system from whence it came.

WHAT MAKES UP THE LYMPHATIC SYSTEM?

It is comprised of several elements - the fluid, cells, vessels, ducts and other organs;

Special structures - lymph nodes, the spleen, thymus, tonsils and adenoids are all components of the lymphatic system.

Functions of the lymphatic system

Filtering of lymph: the lymph nodes act as filters of the lymphatic fluid as it flows through them. White blood cells in the nodes attack any bacteria or viruses found in the lymph. Swollen nodes (wax and kernel) often seen in the neck, groin or armpit are indicative of inflamed or blocked lymph nodes.

Cancer cells that break away from a tumour, often become lodged in nearby lymph nodes. Because of this doctors examine the lymph nodes in cancer patients when looking for evidence of spread.

Filtering the blood: The spleen filters the blood to remove old red blood cells and destroy them. New red blood cells made in the bone marrow will replace them. The spleen also filters out bacteria and viruses allowing the white blood cells to destroy them.

Fighting infection: The lymphatic system helps fight infection by helping to make special white blood cells called lymphocytes and using the nodes and spleen as filters. Thus the lymphatic system functions as a part of the immune system.

THE FLOW OF LYMPH

If the flow of lymph is impaired, the parts of the body that are affected become congested and fill up with their own waste. This otherwise healthy fluid now becomes a potential breeding ground for infection. Wherever fluid stagnates in the body, infection often follows. Many viruses, bacteria and parasites may remain trapped within the lymphatic system when proper drainage is absent. This results in physical ailments, degenerative disease and accelerated ageing.

Many people have congested lymphatics without knowing it. We often overlook the lymphatic system's critical role in preventing disease and promoting healing. In fact the lymphatic system may well be the most over-looked system of the human body.

Lymphoedema is the medical term for swelling that results from blockage of the flow of lymphatic fluid. A common example of this is the swelling of the arm that often occurs after breast surgery for breast cancer. Because the lymph nodes in the armpit are often removed as part of the surgery, this interrupts the normal flow of lymph from the arm.

An even more exaggerated form of lymphoedema occurs in a condition called elephantiasis where the leg may become so swollen with dark thick skin reminiscent of the leg of an elephant. This is due to the blockage of the lymphatic vessels draining the leg by a parasitic worm called filarial.

HOW TO IMPROVE LYMPHATIC CIRCULATION

EXERCISE: As the lymphatic circulation has no pump like the heart, it depends on the movement of the body and the contractions of the muscles to move the lymph. Physical exercise greatly enhances lymphatic flow. Elevate affected limbs.

DEEP BREATHING: Each time you breath in, a negative pressure is created in the chest and lymph is sucked up from the abdomen and extremities back into the blood circulation.

REBOUNDING: This is a special form of exercise using a small trampoline called a rebounder. The vibrations and shock waves created by this form of exercise powerfully enhances the flow of lymph.

MASSAGE: Massage in general but particularly lymphatic massage is wonderful in preventing and treating lymphoedema. Lymphologists are specially trained in using this technique along with decompression bandages to facilitate drainage.

HOT and COLD TREATMENTS: This may include infra red saunas or hot baths alternating with cold water soaks. The relaxation and contraction of the vessels from the fluctuating temperatures enhance lymph drainage.

GOOD NUTRITION: Good cellular nutrition with adequate proteins and lots of vegetables and fruit along with a good fluid intake are essential for a healthy circulation.

SUPPLEMENTS: The omega 3 fatty acids and the anti-oxidants will reduce inflammation and improve the tone and strength all of the blood and lymphatic vessels.

TREAT THE UNDERLYING CAUSE: Remember, it is important to determine and treat the underlying problem and not just the symptom. A sluggish lymphatic system may be a symptom of a potentially serious condition. Treat the cause.

You may email Dr Vendryes at vendryes@mac.com, or listen to An Ounce of Prevention on POWER 106FM on Fridays at 8 p.m. The programme streams live on the Internet.