Explainer | The lymphatic system: how it works, lymphoma and other causes of swollen lymph nodes, and how to safeguard your health – experts explain

The lymphatic system helps the body rid itself of impurities, and problems with it can lead to health issues, from weight gain to joint pain and even cancer

Two experts talk about how obstruction can lead to different kinds of swelling, treatments for various issues, and how to keep your lymph nodes working properly

Reading Time:4 minutes

Swollen lymph nodes are a common sign of problems with the lymphatic system. Experts explain about the body’s “drainage system” and how to keep it working properly. Photo: Shutterstock

Published: 7:15pm, 27 May 2023

The lymphatic system is a network of tissues, vessels and organs working together to move a colourless, watery fluid called lymph back into the bloodstream.

Essentially a drainage network, it forms the foundation of our health and wellness.

About 20 litres (40 pints) of plasma flow through the body’s arteries, blood vessels and capillaries every day, delivering nutrients to cells and collecting their waste products.

Most of the plasma returns to circulation through the veins. But about three litres seep through the capillaries into the body’s tissues.

A diagram of the human lymphatic system. Photo: Shutterstock

The lymphatic system collects this fluid, now called lymph, and carries it along until it’s returned to the bloodstream.

When any of the pathways are not working properly – imagine a blocked drain – we may suffer from swelling and fluid retention, hormone imbalance, gut issues, joint pain, and weight gain, says Michell See, a lymphatic drainage massage therapist at holistic medical practice Balance Health in Hong Kong.