Lymph nodes are small, round organs that are part of the immune system. They filter lymph fluid to remove bacteria and cancer cells and store white blood cells.
Lymph nodes are soft, bean-shaped organs generally less than 1 centimeter in size. They are made up of connective tissue and contain white blood cells (also called lymphocytes).
Hundreds of lymph nodes are located throughout the body, with each cluster responsible for draining lymph fluid from a specific region.
While they are not all physically noticeable, you may be able to feel certain lymph nodes through the skin in prominent areas, such as your:
- Armpits
- Groin
- Back of the head
- Behind the ears
- Underneath the chin and jaw
- Front, sides, and back of the neck
When lymph nodes swell and grow larger than 1 centimeter, it’s called lymphadenopathy. This typically occurs when your body is fighting an infection, cancer, or an autoimmune disease. It may also happen due to certain medications or for no clear reason.
Lymph nodes are part of the lymphatic system. This network of organs and lymph vessels plays a key role in the immune system, the body’s defense mechanism against disease and other foreign invaders.
In particular, they:
- Filter through lymph fluid for signs of infection or other invaders, like cancer cells
- Use white blood cells to identify the abnormalities or threats
- Eliminate any damaged or harmful cells that have been found in the lymph fluid
When lymph nodes become swollen, it typically means they are producing white blood cells to fight off an infection, inflammation, or a potential illness.
Lymph nodes are part of the lymphatic system and are linked to various conditions. Common ones include:
- Lymphadenopathy: This occurs when your lymph nodes make more white blood cells to combat infection or illness. Bacterial or viral infections are typical causes, but it can also result from lymphoma (cancer) or other diseases. Swollen lymph nodes may feel tender or warm, and you might have fatigue or fever.
- Lymphedema: This condition causes ongoing swelling or build-up of lymph fluid under the skin. It commonly causes symptoms like swelling, discomfort, and skin changes in the arms, hands, legs, or feet. People with some types of cancer who receive radiation or surgical treatment involving the lymph nodes often have lymphedema, though it can also develop as a result of factors such as infections, injury, and heart disease.
- Lymphoma: Cancers that develop in the lymph nodes or lymph tissue are known broadly as lymphoma. The two primary subtypes of lymphoma are Hodgkin lymphoma and non-Hodgkin lymphoma. In addition to swollen lymph nodes, other lymphoma symptoms include unintentional weight loss, night sweats, fever, and chills. A weak immune system or certain infections may increase your risk of developing lymphoma.
If you have swollen lymph nodes or if a doctor is concerned, they will likely perform a physical exam. This helps them check for swelling, tenderness, and inflammation. They will also assess your vital signs and ask about your medical history and symptoms.
After a doctor learns about your symptoms, they can order other diagnostic tests to assess the overall health of your lymph nodes and check for any concerns.
Common tests include:
- Imaging scans to check the size of your lymph nodes
- Lymph node biopsy to confirm why your lymph nodes are swollen or functioning improperly
- Blood tests to analyze the number of white blood cells in your body and detect certain conditions, like lymphoma
Experts recommend prioritizing the lymphatic system’s overall health to keep your lymph nodes healthy. Your lymphatic system relies on muscle contractions and active movement (like exercise, limb elevation, and massage) to maintain proper lymph drainage.
You can proactively support the lymph nodes and their function by encouraging healthy lymphatic and immune system functioning by considering the following:
- Get regular exercise or physical activity each day.
- Eat nutritious foods and follow an anti-inflammatory diet.
- Drink plenty of water to support lymphatic drainage.
- Sleep 7-9 hours per day to help the body drain lymphatic fluid naturally at night.
- Limit exposure to harsh cleaning products or pesticides, which can affect immune health.
