What does it do?

The lymphatic system carries lymph fluid, nutrients, and waste material between the body tissues and the bloodstream. It's made up of a network of lymph nodes and vessels in the body.

• Lymph nodes are small, bean-shaped glands. They filter lymph fluid and trap bacteria, viruses, and other substances. White blood cells called lymphocytes then destroy these trapped substances.
• Lymph vessels carry the lymph fluid through the body.

This system is also part of the immune system. Your immune system helps your body fight disease.

What might happen?

When there is a problem in the body, such as an infection, the nearby lymph nodes may swell. The three most common sites of swollen lymph nodes are the neck, armpit, and groin.

The infection might come from a virus, like a cold, or an injury, like a cut.

Lymph nodes in more than one area of the body may also swell. This may be caused by a viral infection, such as mononucleosis, or a bacterial infection, such as strep throat.

Other problems with the lymphatic system include lymphedema and some types of cancer like lymphoma. Other types of cancer can also spread through the lymphatic system.