If there is such a thing as the “Rodney Dangerfield” of body systems, it has to be the lymphatic system. The role of the lymphatic system in health is glossed over in medical school curriculums, passing the lips of most practicing physicians only when discussing disease (lymphedema, lymphadenitis, lymphoma), rarely receiving mention for its vital, health-promoting functions.
The lymphatic system consists of lymph fluid, vessels, valves, more than 400 nodes, two tonsils, the thymus gland and the spleen. About 10 percent of the fluid that passes through the tiniest blood vessels called capillaries becomes trapped in our tissues. This daily accumulation of about one-and-a-half liters of trapped fluid would be our demise if the lymphatic system did not collect it and return it to the circulatory system through lymphatic vessels. Most lymph is clear, with the exception of that absorbed from the small intestinal area. It is called chyme and is milky in color because of the fat molecules it contains.
Unlike the circulatory system that has a pump (the heart), lymph flows as a result of filtration pressure, breathing, gentle movement, and pulsation of neighboring blood vessels. Once mobilized, lymphatic fluid reenters the circulatory system by eventually draining into major veins located in the upper chest region. The largest lymphatic vessel in the body is the thoracic duct. It is located in the left chest/abdominal area, and most of the body’s lymph is funneled into it. The spleen is the largest lymph node or gland.
The lymphatic system is where front line immune activity occurs. Its circulating cells, notably white blood cells or lymphocytes, gather and flow in the lymphatic vessels. It is here that surveillance and destruction of foreign invaders such as bacteria and viruses occurs through antibody production and activity. Toxins are also removed from the body through lymphatic fluid. Though there are some rare genetic diseases of the lymphatic system, most people become aware of this body system through the experience of having a superficial swollen lymph node in their neck, armpit, or groin that accompanies an infection. This swelling is called lymphadenitis, a medical term for inflammation of a lymph node, and is usually a sign that the immune system is doing its job of recognizing and combating infection. A swelling of a limb called lymphedema results when the flow of lymph is impeded either through a birth defect or more often as a side effect of surgery, radiation or trauma. As many as 30 percent of women having a mastectomy will, for example, have lymphedema of the affected arm. Restricted lymph flow and accumulation of toxins in the breast can result from bras that are too tight.
Lymphoma is a malignant overproduction of white blood cells that may become apparent by the appearance of swelling in superficial lymph nodes in the neck or groin or an enlarged spleen. Not all cancers in lymph nodes are lymphomas. Cancer cells can migrate through the lymphatic system, resulting in non-primary lymph node cancers such as breast or colon cancer spreading to local or regional lymph nodes.
Because immunity and surveillance of cancer cells have their origins in the lymphatic system, further research in understanding the lymphatic system’s important functions may hold clues to more effective treatment of all cancers, autoimmune diseases, and overall immune function.
Tactics to facilitate good lymphatic flow and function include deep breathing from the diaphragm, gentle bouncing on a rebounder (small trampoline), stretching, dry brushing of the skin with a soft brush (always brushing toward the heart), exercise, and avoiding obesity. Don’t wear restrictive undergarments, clothing, or belts. Certified lymphatic massage therapists can gently assist the flow of stagnant lymphatic fluid. Check with your medical healthcare provider before starting any new treatment.