A Little About the Lymph . . . It’s a Circulatory System

You may have heard about the lymphatic (lymph for short) system before, and heard it in relation to the immune system. Sometimes when you’re sick your tonsils or little “nodes” around your throat or ears can swell up. These are part of the lymph system, and they do play a role in fighting off pathogens. But did you know that your lymph system is vast, like a huge highway system, with organs and outposts all around the body? Yep, it’s pretty amazing. It works with the cardiovascular and immune systems, with the lymph vessels running alongside veins, picking up the fluid that leaks out of capillaries. (Don’t worry, fluid leaking out of capillaries in this case is normal!)


  1. The lymph system is a highway, right? And what are highways for? Transportation! In the case of lymph, it’s a way to transport what the body no longer needs (waste products), dietary lipids like vitamins D and K, proteins and other large molecules, like immune cells.
  2. As mentioned before, the lymphatic system picks up fluid in the tissues, helping to maintain fluid balance in the body. If parts of the lymph system are compromised, fluid can build up in the tissues, causing swelling.
  3. The lymph system also helps start the body’s immune response! In fact, one important lymph organ (the thymus) is responsible for maturing T-cells and releasing them into the body to fight germs.

The Lymphatic Highway’s Interstates and Routes

If you want to understand the smaller parts of the highway, we have to start with where all the roads lead:

The right lymphatic duct and the thoracic duct.

These two ducts are located above the heart, near the subclavian veins (which are under your collar bones). All lymphatic vessels go one way, toward these ducts so that all the stuff in the lymph vessels can go back into the circulatory system.

Capillaries to Vessels to Nodes to Vessels to Ducts

Way out in your tissues are tiny lymph capillaries that absorb fluids that leak out of blood capillaries. These lymph capillaries lead to bigger roads, known as lymph vessels. These vessels travel near veins, and have lots of valves that prevent the fluid from back-flowing.

Lymph vessels have stops along the way, small organs that are encapsulated and anchored in place. These small organs are called nodes, and they are a filter of sorts. They also have immune cells living in them (B cells, T cells and macrophages), that can be called to action when needed.

From the nodes, vessels travel to the ultimate goal, the right lymphatic and the thoracic duct.

Photo courtesy of the Mayo Clinic

Lymph Organs and Outposts

There are two big organs of the lymph system.

  1. The thymus, which is found behind your breast bone, is in charge of unleashing mature T-cells. It also secretes the hormone thymosin, which is the substance that turns immature T-cells into the real fighting machines they need to be for our immune system’s arsenal.
  2. The spleen is the largest lymphatic organ. It filters blood and lymph and is involved in the immune response.

The appendix of the colon has been found to be a part of the lymphatic system as well. It’s not quite the “useless” organ medicine originally thought it was!

You also have some pretty amazing lymphatic outposts all around your body, because let’s face it, the body is a huge place. It needs these outposts to help defend your body against pathogens. Outposts include:

  1. Your tonsils, which are considered nodules
  2. Peyer’s Patches, which are a cluster of nodules in the small intestine that help prevent pathogens from attacking your intestines
  3. Mucosa Associated Lymphatic Tissue (MALT) are tissues that form near mucous membranes. MALTs can come and go as needed. They’re like PRN nurses; activity (germs, usually) stimulate their appearance.

How to Stimulate the Lymphatic System

You can help keep lymph moving freely through your body with a few simple things.

  1. Movement! Moving your body has always been an important part of your health. When your muscles contract and relax, it helps pump lymph along its vessels.
  2. Hydration is huge for proper lymphatic movement. You need fluid to move all those proteins and immune cells through the lymph, right? So be sure to drink enough water throughout the day.
  3. Massage is a great, and super relaxing, way to move lymph back toward those lymphatic ducts. Swedish massage, which is light with movements that aim toward the heart, can stimulate the movement of lymph. Lymphatic massage, which is a highly specialized form of massage that focuses on moving lymph specifically, is recommended for anyone who wants or needs to move lymph fluid back to the lymph ducts. If you have lymphedema, you will want to see a massage therapist who is certified in lymphatic drainage.
  4. Hot/cold contrast baths stimulate contraction and dilation of blood vessels, which can help pump lymph along its vessels.
  5. Dry skin brushing, which is performed with strokes that go toward the heart, physically encourages lymph to go back to the heart.

Although there is so much more to the lymphatic system, the basics are fairly easy to understand. Now when your doctor talks to you about some of your lymph nodes or organs, you’ll know what they do! And maybe you’ve learned to appreciate a little more what your body does for you on a daily basis. All these amazing systems and organs working hard to keep you healthy. All they need is for you to do a few simple things to keep them healthy in return.