Your lymphatic system, part of your immune system, performs many roles. They include protecting your body from bacteria and cancer cells, maintaining body fluid levels, absorbing digestive tract fats and removing cellular waste. Blockages, diseases or infections can affect your lymphatic system’s function.

The lymphatic system is a complex network of tissues, vessels and organs that work together to move lymph back into your bloodstream. The lymphatic system is part of your immune system.

What is the lymphatic system?

The lymphatic system is a network of tissues, vessels and organs that work together to move a colourless, watery fluid called lymph back into your circulatory system (your bloodstream).

Some 20 litres of plasma circulate through your body’s arteries, smaller arteriole blood vessels and capillaries every day. After delivering nutrients to the body’s cells and tissues and receiving their waste products, about 17 litres are returned to the circulation by way of veins. The remaining three litres seep through the capillaries and into your body’s tissues. The lymphatic system collects this waste fluid, now called lymph, from tissues in your body and moves it along until it's ultimately returned to your bloodstream to be cleaned.

The Lymphatic system also helps to absorb fats from your digestive tract through the Peyer’s patch and transports it back to your blood stream.

Importantly it is an integral part of your immune system, protecting your body against foreign invaders.  It produces and releases lymphocytes (white blood cells) and other immune cells that monitor and then destroy foreign invaders such as bacteria, viruses, parasites, and fungi that may enter your body. It is also vital in not only clearing waste products that the cells produce but also clearing abnormal cells from the body.

The lymphatic system consists of many parts. These include:

• Lymph:Lymph, also called lymphatic fluid, is a collection of the extra fluid that drains from cells and tissues (that is not reabsorbed into the capillaries) plus other substances. The other substances include proteins, minerals, fats, nutrients, damaged cells, cancer cells and foreign invaders (bacteria, viruses, etc). Lymph also transports infection-fighting white blood cells (lymphocytes).

• Lymph nodes:Lymph nodes are bean-shaped glands that monitor and cleanse the lymph as it filters through them. The nodes filter out the damaged cells and cancer cells. These lymph nodes also produce and store lymphocytes and other immune system cells that attack and destroy bacteria and other harmful substances in the fluid. You have about 600 lymph nodes scattered throughout your body. Some exist as a single node; others are closely connected groups called chains. A few of the more familiar locations of lymph nodes are in your armpit, groin and neck. Lymph nodes are connected to others by the lymphatic vessels.
• Lymphatic vessels:Lymphatic vessels are the network of capillaries (micro vessels) and a large network of tubes located throughout your body that transport lymph away from tissues. Lymphatic vessels collect and filter lymph (at the nodes) as it continues to move toward larger vessels called collecting ducts. These vessels operate very much like your veins do: They work under very low pressure, have a series of valves in them to keep the fluid moving in one direction.
• Collecting ducts:Lymphatic vessels empty the lymph into the right lymphatic duct and left lymphatic duct (also called the thoracic duct). These ducts connect to the subclavian vein, which returns lymph to your bloodstream. The subclavian vein runs below your collarbone. Returning lymph to the bloodstream helps to maintain normal blood volume and pressure. It also prevents the excess build up of fluid around the tissues (called oedema).
• Spleen: This largest lymphatic organ is located on your left side under your ribs and above your stomach. The spleen filters and stores blood and produces white blood cells that fight infection or disease.
• Thymus: This organ is located in the upper chest beneath the breast bone. It matures a specific type of white blood cell that fights off foreign organisms.
• Tonsils and adenoid: These lymphoid organs trap pathogens from the food you eat and the air you breathe. They are your body’s first line of defense against foreign invaders.
• Bone marrow:This is the soft, spongy tissue in the center of certain bones, such as the hip bone and breastbone. White blood cells, red blood cells, and platelets are made in the bone marrow.
• Peyer’s patches: These are small masses of lymphatic tissue in the mucous membrane that lines your small intestine. These lymphoid cells monitor and destroy bacteria in the intestines.
• Appendix: Your appendix contains lymphoid tissue that can destroy bacteria before it breaches the intestine wall during absorption. Scientists also believe the appendix plays a role in housing “good bacteria” and repopulating our gut with good bacteria after an infection has cleared.

How can I keep my lymphatic system healthy?

To keep your lymphatic system strong and healthy, you should:

• Avoid exposure to toxic chemicals like those in pesticides or cleaning products. These chemicals can build up in your system and make it harder for your body to filter waste.
• Drink plenty of water to stay hydrated so lymph can easily move throughout your body.
• Move your lymphatic system with the right kind of movements (Gyrotonic / Gyrokinesis) and self massage especially of the breast tissue.
• Maintain a healthy lifestyle that includes regular exercise and a healthy diet.
• The lymphatic drainage of the breast flows toward the axillary and internal mammary lymph nodes.

Reproduced with permission from: Moore KL, Agur A. Essential Clinical Anatomy, Second Ed. Philadelphia: Lippincott Williams & Wilkins, 2002. Copyright © 2002 Lippincott Williams & Wilkins.