Although it doesn’t get nearly the attention of the cardiovascular system, the lymph system also deserves top billing for the role it plays in keeping things running smoothly.
This system, which distributes a fluid called lymph, not only supports immunity but also influences fluid balance and even the absorption of fats and such fat-soluble nutrients as vitamins A and D.
“The lymph system is often described as a sort of ‘add-on’ to the venous side of the circulatory system, in that one of its main functions is the return of fluids from the cells and tissues to the blood circulation,” says Pip Waller, medical herbalist and author of The Herbal Handbook of Home and Health (North Atlantic Books).
The lymph system helps keep the fluid that bathes the body’s cells in circulation. As Waller puts it, “The cells take the nutrients and replace them with waste plus whatever products they make. These need to find their way back into the blood to be circulated all around the body. Whatever can’t get into the venous capillaries enters the lymph capillaries instead.”
Although they sound as if they perform similar functions, the blood and lymph systems function differently. “Tiny lymph vessels are more permeable than blood capillaries to allow larger particles, such as dead cells and bacteria, to enter them,” explains Waller.
What’s more, unlike the cardiovascular system, the lymph system does not have a direct way of moving lymph; it has no central pump analogous to the heart. It instead must rely on muscular contractions of the lymphatic vessel wall to squeeze fluid along and prevent backup. In addition, the one-way valves in all of the lymph system’s vessels mean that fluid can only move towards the heart.
Along the way, the lymph passes through lymph nodes. These filter out harmful substances and contain immune cells that can attack microbes carried in through the lymph.
When lymph does not keep moving, fluid builds up in tissues to create edema; it is a common cause of swollen ankles in people sitting for long hours, such as on a flight. “Poorly moving lymph also means that we are not able to properly clean up the body,” says Waller. “We become more toxic, and are less able to repair and rejuvenate the body properly. The immune system is impaired.”
Since muscular contraction helps lymph fluid move, it makes sense that exercise performs a vital role in supporting the lymph system.
“Practices such as qigong, tai chi, daoyin [an ancient Chinese body-mind exercise] and yoga help to move fluid through gentle movements, which act almost like a massage for the whole body,” says Chinese medicine doctor Nini Mai, DACM, clinic director at Evolve Health & Wellness in New York City. She explains that flexing and extending the joints and muscles, and alternating between contraction and relaxation, allows blood and lymph to flow through blood vessels and the body’s connective tissue networks.
Yoga works in much the same way. In addition, many poses call for elevation of the limbs, which also helps lymph to flow. What’s more, practicing yoga regularly reduces inactivity, which can lead to edema. (Three yoga poses recommended to reduce leg swelling include Boat, Locust and Supported Shoulder Stand.)
Massage and acupuncture help keep lymph moving. “Any massage has a beneficial effect,” says Waller, “but to specifically help the lymphatic circulation, go for manual lymphatic massage. Lymph massage involves a very light touch, to encourage the movement of lymph through the multitude of vessels that lie just under the skin.”
Waller also recommends dry brushing once or twice a day for a month, using a brush with a long handle to reach all over. Lightly brush with a combination of short and long strokes, and always towards the heart. This is best done for five minutes before a shower.
In addition, acupuncture is believed to reduce inflammation by encouraging the movement of blood and fluids, Mai says, adding, “Certain Chinese herbs and formulas can help regulate the movement of blood and fluids in the body.”
No matter how you do it, making your lymph move is essential to keeping you moving as well.