Importance and Overview of the Lymphatic System
The lymphatic system is absolutely essential for immediate and long-term health and requires support. Despite its crucial role, the lymphatic system is somewhat cryptic and does not receive as much attention as the cardiovascular system, brain and nervous system, or even the gut microbiome.
Structure, Function, and Drainage
The lymphatic system functions as a necessary "third system" because the blood circulatory system is not perfect. After the arterial system delivers oxygenated blood, nutrients, and water to the tissues, and the venous system collects deoxygenated blood and some waste, about 3 to 4 litres of excess fluid and cellular waste products remain in the interstitial (extracellular) space.
- Function: The lymphatic system is responsible for taking this remaining fluid ("lymph") and "gunk" (proteins, ammonia, carbon dioxide, cellular waste) and bringing it back to the blood supply.
- Consequences of Failure: If this fluid and waste are not cleared, they accumulate, creating an environment ripe for infection and inflammation. Lack of clearance can lead to localised or systemic inflammation, thickening of skin and adipose tissue, and, specifically in the brain, rapid and severe brain fog.
- Vessel Characteristics: Lymphatic vessels are present everywhere in the body, including the skin, fat tissue, and brain. Crucially, they are one-way vessels, meaning fluid can only pass in one direction—towards the heart.
- Lack of Pump: Unlike the cardiovascular system, which has the heart, the lymphatic system is a passive system with no pump, and it must constantly fight gravity to move lymph fluid along.
- Drainage Site: Lymphatic fluid eventually returns to join the blood supply at two major ducts: the right lymphatic duct (draining the upper right quadrant of the body) and the thoracic (left) lymphatic duct (draining the rest of the body). Both ducts dump into the subclavian veins (below the collar bones).
Protocols for Encouraging Lymphatic Flow
Since the system lacks a pump, the movement of lymph relies on external forces:
- Muscular Movement: Lymph is moved through the vessels by low-level muscular contractions created by everyday activities like walking, standing up, or making micro-movements. The lymphatic vessels (especially deeper ones) are closely related to the fascia surrounding muscles, ensuring that movement carries the fluid along. Striving for at least 7,000 steps per day is suggested to encourage drainage.
- Diaphragmatic Breathing: This is highly effective for improving the rate and extent of lymphatic drainage. Diaphragmatic breathing (inhaling deeply so the belly moves out) creates a pressure differential that encourages lymph to move from the large abdominal reservoir called the cisterna chyli back into the blood supply.
- Rebounding and Shaking: Activities like jumping on a small trampoline, shaking, swimming, or treading water are effective because the one-way nature of the vessels ensures that, regardless of the direction of the force (like stamping down), the fluid moves upward. Swimming is excellent because the shearing effect of the water squeezes the superficial vessels under the skin.
- Hydration: Drinking sufficient water supports proper blood volume and improves lymphatic flow and drainage, which helps clear water retention and oedema.
- Cardiovascular Exercise and Heart Health: Some of the benefit of aerobic exercise for the heart occurs because it stimulates lymphangiogenesis (the growth of new lymphatic vessels). This growth and remodelling of vessels allows for increased clearance of waste products from heart cells, offsetting inflammation often associated with the ageing heart.
Lymphatic Massage and Pressure Application
Lymphatic massage is used frequently in medical practice, particularly for treating lymphedema (swelling due to impaired drainage).
- Light Touch is Key: Lymphatic massage must be intentionally rather light, involving gentle rubbing, shearing of the skin, tapping, or padding. Deep tissue massage is counterproductive, as the strong pressure can cause the tiny, small-diameter lymphatic capillaries to collapse or rupture.
- Drainage Encouragement: Protocols usually involve encouraging movement of fluid toward the drainage sites, specifically the clavicle region and the cisterna chyli.
- Avoid Lymph Nodes: Professionals generally advise against massaging lymph nodes directly because they are sites where the immune system sequesters lymph for surveillance and battles infections.
- Cosmetic Applications: Techniques for the face, such as those using gentle pressure or rollers, are effective because the lymphatic capillaries around the eyes and face are tiny and benefit from gentle pressure in the proper order and direction to encourage clearance out of the head and neck.
Immune System Role and Lymphedema
The lymphatic system serves a secondary, vital role in immune surveillance. Lymph nodes are compartments along the vessels where the lymph fluid is temporarily sequestered and monitored. Immune cells (T-cells, B-cells, lymphocytes) within the nodes inspect the fluid for foreign invaders such as viruses, bacteria, and other contaminants that may have entered the blood supply. Swollen lymph nodes are a sign that the immune system is actively combating or evaluating something.
Lymphedema is the accumulation of fluid and waste in the interstitial space due to insufficient drainage. It often occurs in cancer treatment when lymph nodes or vessels are intentionally destroyed to prevent the metastasis (spreading) of cancer cells. The resulting buildup causes local inflammation, tissue thickening, and hypoxia (low oxygen availability), making clearance increasingly difficult.
The Glymphatic System and Brain Drainage
The brain's lymphatic drainage system is called the glymphatic system, which was formally verified in 2012.
- Mechanism During Sleep: Waste products from metabolically active brain cells are collected by cerebral spinal fluid (CSF). During sleep, specific glial cells called astrocytes push out, causing the perivascular space (the area around the blood vessels entering the brain) to increase in size by 60%. This expansion, along with the activation of the channel Aquaporin 4, allows the CSF carrying the waste products to flow out of the brain and into the venous blood supply.
- Impaired Clearance: If a person gets insufficient sleep, this clearance process does not fully occur, leading directly to brain fog and cognitive impairment. Chronic impairment of glymphatic clearance is associated with the buildup of inflammatory molecules and proteins like amyloid plaques, which are linked to diseases like Alzheimer's.
- Optimal Sleep Position: Studies suggest that sleeping on your side is the optimal position for humans to encourage efficient glymphatic drainage.
- Supporting Protocols: To improve glymphatic clearance, strategies include side sleeping, elevating the feet slightly (5 to 10 degrees), ensuring the head is slightly tilted up (often accomplished by a pillow), and avoiding alcohol intake prior to sleep (as it reduces REM sleep, impairing clearance).
The Role of Long Wavelength Light
Exposure to long wavelength light (red light, near infrared, infrared, typically 620 to 1,000 nanometers) can penetrate deep into the skin. This light improves mitochondrial function in cells. Exposure to long wavelength light, either from specialised devices or from low solar angle sunlight (sunrise/sunset), can reduce inflammation, improve skin appearance, and reduce lymphedema. This positive effect is achieved in part by improving the function of the lymphatic system, as well as blood flow and direct effects on skin cells.