Corpus: Lymph

Lymph' is a watery, slightly milky, cloudy body fluid found in the lymphatic vessels of the body. It contains electrolytes, proteins, chylomicrons and white blood cells (lymphocytes). However, its protein content is significantly lower than that of blood plasma.

The fat-rich, cloudy lymph from the gastrointestinal tract is known as chyle.

Lymph is formed from extracapillary fluid that escapes into the intercellular space during the passage of blood through the blood capillaries and is not reabsorbed by the venous branch of the blood circulation. However, intercellular fluid and lymph are not identical, as waste products accumulate in the lymph that are to be removed from the intracellular space.

The lymph initially collects in the lymphatic capillaries, which join together to form larger lymphatic vessels. Lymph nodes, which serve to filter the lymph or immune defence, are located at certain points along the lymphatic pathway. Before flowing through a lymph node, the lymph is referred to as primary lymph, afterwards as secondary lymph.

In addition to its "detoxifying" function, lymph plays an important role in tissue drainage, as it drains excess tissue fluid into the lymph vessels. The amount of lymph produced daily is around 2-3 litres. If lymph drainage is impaired, lymphoedema occurs.

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