Lymph nodes are part of the lymph system, which carries lymph fluid, nutrients, and waste material between the body tissues and the bloodstream. The three most common sites of swollen lymph nodes are the neck, armpit, and groin. The lymph system is also an important part of the immune system, the body's defense system against disease.
Current as of: May 1, 2026
Author: WebMD Ignite Staff
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