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Lymphocyte Percentage

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All NiaHealth tests are processed in Canadian-certified labs, which are highly trusted by the medical community for their accuracy and reliability. Blood and urine samples are collected by licensed medical professionals and processed using state-of-the-art equipment. NiaHealth is SOC2 Type 2 certified.

What is it?

Lymphocyte percentage shows what portion of your white blood cells are lymphocytes. These are the cells that run your body's targeted, long-lasting immune response. They remember past infections and are the reason vaccines work. Unlike neutrophils, which live for only a few days, lymphocytes can survive for years.

Why it matters

Before modern analysers, lymphocyte percentage was one of the main ways to tell a viral infection apart from a bacterial one. A high percentage often pointed to a virus; a low one alongside high neutrophils often pointed to bacteria. Those patterns are still useful today, though they are not absolute — some bacterial infections can raise lymphocytes, and some viral ones can raise neutrophils. A genuinely low lymphocyte percentage can be a sign of immune suppression, but it is often misleading. Because all white blood cell percentages must add up to 100%, when neutrophils rise during a bacterial infection, lymphocyte percentage drops automatically, even when the actual lymphocyte count is completely normal.

Reference ranges

This information is educational and does not replace medical advice, diagnosis, or treatment. Your results should be interpreted with a qualified healthcare professional in the context of your health history.