Immune-boosting, nutrient-delivering, waste-removing, blood-cleansing lymph
How Does the Lymphatic System Work?
The cells of the body are bathed and surrounded by interstitial fluid, which is a water solvent containing amino acids, hormones, neurotransmitters, fatty acids, sugars, salts, and waste products from the cells. This fluid, called lymph, provides the platform for delivering materials to the cells and removing metabolic waste. This fluid also contains white blood cells to help combat infection.
One of the easiest ways to visualize the working of the lymph is to compare it to your local trash-collection service. It generally runs smoothly: the trucks come regularly and gather up the bags, tins, boxes, and other bits and take them away to be sorted and disposed of at a central processing plant. If the roads are well maintained and nothing gets in the way, it all happens swiftly and efficiently.
Imagine that the street is in disrepair and the trucks cannot move as quickly. Getting the rubbish off the street takes longer, and it begins to decompose in the sun. Likewise, when we are sedentary, the lymph does not get the activation it needs for good circulation, and waste builds up. Also, being dehydrated is akin to big potholes in the road, as the trucks (lymph) cannot move freely.
Now suppose some of the trucks are permanently taken off the garbage route. This is what happens when lymph nodes are removed during surgery, as is often the case with breast cancer surgery. How many lymph nodes are removed depends on the surgery and will determine how much extra support you need to give your lymph system to ensure that all your body’s waste products are still being collected.
With fewer lymph nodes, you now require a different strategy to remove the rubbish with fewer trucks. It is critical that you keep the roads clear and in good repair to facilitate the efficiency of the trucks you still have. Stimulating the areas of high lymph node concentration will help the body stay on top of waste removal. One point of interest: lymph fluid travels in one direction only, with backflow being prevented by single-direction flap valves in the lymph vessels. This stops the waste from going the wrong way into the blood before it has been cleaned.
Unlike the circulatory system, in which the heart pumps the blood, the lymphatic system has no such pump and relies instead on muscular contraction (i.e. movement and exercise) to move the fluid around the body. The vast network of lymph vessels flows against gravity as well, providing just that extra little challenge. Fortunately there are many ways to stimulate the lymphatic system, and I’ll explain these methods later.
Why Is the Lymphatic System So Important?
- Healthy tissue drainage: Every day about 21 liters (equal to 88 cups, 5.5 gallons, or 22 quarts) of plasma fluid carrying dissolved substances escape from the arterial end of the blood capillaries and into the tissues. Most of this fluid returns directly to the bloodstream, but 3 to 4 liters of fluid are drained away by the lymphatic vessels. The body’s waste materials are removed by the lymph to prevent them from recirculating into the blood.
- Nutrient absorption in the small intestine: In the small intestine there are finger-like projections called villi, which increase the total intestinal surface area. Within each little villus there is a network of capillaries and lymphatic vessels. Amino acids and carbohydrates are absorbed into the capillaries, whereas fat and fat-soluble materials are absorbed into the lymphatic vessels. Fats are critical to optimal health throughout the body.
- Maintenance of the immune system: The lymphatic organs are responsible for the production and maturation of lymphocytes, the white blood cells primarily responsible for immunity. Lymphocytes fight infection and destroy abnormal or damaged cells. Bone marrow is considered lymphatic tissue because lymphocytes are made in bone marrow.
- Defense again antigens: Lymph fluid plays a vital role in protecting the body from foreign materials known collectively as antigens. The immune system dispatches cells called phagocytes via the lymph system. These cells act like a Pac-Man, engulfing and trapping the antigens and releasing them when they come into contact with the white blood cells designed to destroy them.
Components of the Lymphatic System
The lymphatic system is made up of both deep and superficial vessels. The deep vessels generally follow the deep veins of the circulatory system, while the superficial vessels are in the superficial fascia. Lymph passes through vessels of increasing size and several lymph nodes (small, round, filter-like organs) before returning to the blood. Think of the lymph nodes as filtration plants where unwanted bacteria, viruses, and other wastes are attacked and destroyed by the immune cells stationed there. The cleansed fluid then returns into circulation.
The fluid that runs through the system, lymph, travels through tubes called lymph vessels. You may be surprised to learn that the volume of lymphatic fluid in the body is about double that of blood. There are also roughly twice as many lymph vessels as there are blood vessels, so it is a significant body system.
There are three main areas of lymph node concentration where waste materials are removed from the lymph before the fluid returns into circulation. In the neck we have the cervical lymph nodes, (not indicated in the figure above), in the armpits are the axillary lymph nodes and in the groin are the inguinal lymph nodes.
Focused exercise in these three main areas helps cleanse the lymph and keep immunity strong. Other organs involved in the lymphatic system include the thymus gland, the spleen, and diffuse lymphoid tissue such as the tonsils and adenoids. Finally we have lymphatic tissue, which is made in the bone marrow. As you can see, this system is very far reaching.
Immunity and the Lymphatic System
The lymphatic system is an intricate part of immunity. The spleen is the largest lymph organ and is highly active in the body’s defense. The spleen is located above the stomach under the rib cage. Abnormal and old red blood cells are destroyed in the spleen, and the breakdown products are then sent to the liver. Along with the lymph nodes, the spleen creates lymphocytes, which are the body’s defenders. Unlike the lymph nodes, the spleen is not entered by any lymphatic vessels, which protects it from diseases that the lymph fluid is carrying to the nodes for destruction.
The T-lymphocytes (the good guys who gobble up baddies) mature in the thymus. This gland is most active in childhood, and by puberty it starts to atrophy thanks to sex hormones. We stockpile T-lymphocytes as children, and the thymus degenerates to the point of being a blip of fat, which potentially contributes to susceptibility to infection and cancer when the person ages.
The tonsils and adenoids are considered the first line of defense for the respiratory and digestive systems. Waldeyer’s tonsillar ring is an anatomical term collectively describing the arrangement of lymphoid tissue in the pharynx: the space that reaches from the back of the nasal cavity close to the bottom of the throat where food and air go into different tubes—either the esophagus or the trachea.
From the top to the bottom, the ring of lymph tissue has two adenoids (or pharyngeal tonsils) located at the back of the nasal cavity (nasopharynx) where the nose meets the throat, above the oral cavity. Next are two tubal tonsils near where the Eustachian tubes (from the ears) open into the nasopharynx, followed by what most of us call the tonsils, officially known as the palatine tonsils. These are located at the back of the mouth. Finally, there is more lymph tissue in the tongue and throat to complete Waldeyer’s ring.
These lymph tissues defend against bacteria that enter the nose and mouth. They have specialized cells that capture antigens (things we don’t want in our bodies). As they hold them, an immune response is activated, and the B-cells (made in the bone marrow) and T-cells (made in the thymus) come to destroy the antigens. As each antigen is demolished, the B-cells make a memory cell specific to it. If this particular antigen shows up again, the immune system, via the memory B-cell, can get on top of it much faster. This is why it is common to get sick when you travel to foreign countries, as you have no previous exposure to the different antigens, and your body has no memory of how to fight quickly.
Lymph Fluid Drainage
Because the body contains twice as much lymph as blood, it is critical to stay well hydrated in order to keep the immune system working efficiently, which will help you create a good, healthy scar. Your body will let you know if it is dehydrated through the following symptoms:
- bloating and water retention (counterintuitive but true)
- puffy fingers (you may notice rings become too tight)
- itchy skin, dry skin, flaky scalp
- swollen ankles or feet
- feeling stiff and sore when you wake
- cold hands and feet
- tiredness, fatigue, brain fog
- unexplained irritability
- soreness and/or swelling of the breasts before menses
The lymph does not drain symmetrically in the body.
I always found this a fascinating and rather puzzling fact. There are two principle lymph vessels, the thoracic and right lymph ducts, which pour into the heart via the brachiocephalic veins. The lymph returns to these ducts in a peculiar way. The head, neck, and right arm drain into the right lymph duct, whereas the left arm, entire trunk of the body, and both legs drain into the thoracic lymph duct.
This is important to know because it may affect how you encourage lymph flow in the body through exercise. Remember we have three main areas of lymph node concentration: the deep and superficial lymphatic vessels flow through the cervical nodes in the jaw and neck, the axillary nodes in the armpits, and the inguinal nodes in the groin. So suppose you have swollen ankles. You will want to activate the groin and the left axillary nodes more often in order to drain the lymph from the legs. If you have headaches, you will want to pay particular attention to exercising the right arm to drain the lymph fluid from your head and neck.
Bear in mind that if any of your lymph organs have been previously removed (for example a tonsillectomy or adenoidectomy) you need to be more vigilant in taking care of yourself because you have lost some of your immune system’s team members. Besides staying hydrated, there are other ways to help you stay or become healthy both during surgical recovery and well after. These include specific stretches to stimulate the lymph, skin brushing, deep breathing, bouncing on a trampoline, walking and yoga.