Lymph nodes are small, bean-shaped glands that are part of the body’s immune system. While usually unnoticeable, they can sometimes be felt. This often occurs when they are actively protecting the body.
Understanding Lymph Nodes
Lymph nodes function as filters within the lymphatic system, a network of vessels and organs that is part of the body’s immune defense. They are strategically positioned throughout the body, acting as checkpoints for lymph fluid. This fluid carries waste products and potentially harmful substances.
Inside the lymph nodes, specialized immune cells, primarily lymphocytes (B cells and T cells), are housed. These cells identify and neutralize foreign invaders like bacteria, viruses, and abnormal cells. When pathogens are detected, the immune cells in the nodes activate, initiating a defensive response.
Common Locations to Feel Lymph Nodes
Lymph nodes are distributed throughout the body, with hundreds present. Some are situated deeper within the body, such as in the chest or abdomen, and cannot be easily felt. However, many are close to the skin’s surface and can be palpated.
Common areas where lymph nodes can be felt include the neck, under the jaw, behind the ears, and along the sides. They are also palpable in the armpits and the groin area. These superficial locations are often where swelling becomes apparent when the immune system is active.
What Healthy Lymph Nodes Feel Like
It is common for healthy lymph nodes to be felt, especially in individuals with a leaner physique. When palpable, normal lymph nodes are usually small, pea-sized or smaller, ranging from a few millimeters up to about 1.5 centimeters in diameter. They typically feel soft and are movable when gently pressed under the skin.
Healthy lymph nodes are not tender or painful to the touch. They should feel somewhat rubbery, similar to the tip of your nose, but not hard or fixed. The presence of small, non-tender, movable nodes in these common areas is generally a normal finding.
Why Lymph Nodes Swell
Lymph nodes swell when actively fighting an infection or inflammation. This enlargement, medically termed lymphadenopathy, occurs as immune cells multiply and accumulate within the nodes to combat pathogens. The swelling indicates that the body’s immune system is working to clear harmful substances.
Common causes of swollen lymph nodes include viral infections like colds, flu, mononucleosis, and strep throat. Bacterial infections, such as those affecting the ear or skin, can also lead to enlarged nodes. Minor injuries or localized inflammation near a lymph node group can cause the nodes in that area to swell. Swollen nodes often feel larger (pea to bean-sized or larger), firmer, and may be tender or painful to the touch.
When to See a Doctor
While most instances of swollen lymph nodes resolve on their own, certain characteristics warrant a medical evaluation. A healthcare professional should be consulted if a swollen lymph node has no obvious cause or persists for more than two to four weeks. Nodes that continue to grow, feel very hard, or are fixed and do not move when pressed are also concerning.
Other signs that suggest a doctor’s visit is necessary include swollen nodes accompanied by unexplained weight loss, night sweats, or a persistent fever. Painful nodes without an apparent infection, or swelling above the collarbone, are also reasons to seek medical advice. If the skin over the swollen node becomes red or inflamed, or if there is pus drainage, prompt medical attention is advisable.