Lymph is watery fluid that moves through your lymphatic system. Your lymphatic system helps support your overall health. Lymph collects fluids from your tissues and returns them to your blood. It carries nutrients and proteins to your cells and tissues. It also collects any harmful substances found in your cells and tissues.
Lymph is watery fluid that flows through your lymphatic system. Lymph (pronounced “limf”) helps your lymphatic system support your overall health, from providing nutrients to cells and tissues to protecting your body from foreign intruders like viruses, bacteria and cancerous cells.
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To understand what lymph does, it may help to understand how your body creates lymph. That story starts with your circulatory system, which partners with your lymphatic system. Your circulatory system is a network of arteries, veins and capillaries that carry blood throughout your body. Blood contains plasma.
As blood flows through your capillaries, some plasma oozes through tiny holes in your capillary walls. This plasma, now called lymph, moves into your tissues and the spaces around your cells to deliver oxygen, proteins and other nutrients. At the same time, lymph sweeps up debris like damaged and cancerous cells, bacteria and viruses. Lymph also picks up extra fluid from your tissues and cells that your capillaries can’t absorb.
Loaded down with extra fluid and harmful organisms, like damaged or dangerous cargo, lymph then moves into lymphatic capillaries that carry lymph back through your body. As it travels, lymph goes through lymph nodes. Lymph nodes are lymph quality control, searching lymph cargo for harmful organisms to be destroyed by white blood cells (lymphocytes). The filtered lymph eventually returns to your bloodstream.
In a word, lymph is anywhere you have lymphatic capillaries. There are lymphatic capillaries in the tissues of nearly every organ in your body. Your liver and your digestive system produce 80% of lymph in your body. That lymph is called chyle, which contains a mixture of white blood cells and fats that make it look milky.
Lymph typically is clear or colorless, but it can be yellow. Chyle, lymph produced by your digestive system, looks milky.
Lymph needs to keep moving. There are conditions that make that difficult:
Swelling is a common symptom of lymphedema, which happens when lymph fluid can’t flow normally and begins building up in nearby soft tissue.
Taking care of your lymphatic system is the best way to take care of your lymph fluid. To keep your lymphatic system strong and healthy, you should:
No, lymph fluid isn’t the same as lymphocytes, but there may be lymphocytes in your lymph fluid. Lymphocytes are white blood cells that fight infection. Lymph often pick up cancerous cells and intruders like bacteria and viruses, and lymphocytes sometimes dispose of dangerous intruders.
A note from Cleveland Clinic
Lymph is watery fluid that flows throughout your body. It supports your overall health, delivering proteins and nutrients to your blood and helping to dispose of dangerous substances. Conditions like lymphedema happen when something blocks lymph so it builds up in your soft tissues, making them swell.
Last reviewed by a Cleveland Clinic medical professional on 08/22/2023.
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