Lymphocytes
Lymphocytes are the white blood cells responsible for adaptive immunity, including T cells, B cells, and natural killer cells. They are the second most common white cell after neutrophils. The percent-of-WBC view is shown alongside the absolute count.
Unit: 1000 cells/uL · 12 slices · age and sex · 1 source
Filed under panels: Complete Blood Count · topics: Hematology
The absolute lymphocyte count measures circulating lymphocytes (T cells, B cells, and natural killer cells), the cells of adaptive immunity. NHANES reports both a percent of total WBC and an absolute count; this page uses the absolute count in 1000 cells/uL, consistent with the rest of the CBC panel. Lymphocyte counts shift with viral infection, chronic immune activation, and age. The percent-of-WBC distribution is also shown: the share of total white cells that are lymphocytes, from the NHANES lymphocyte percent variable.
Population Distribution
Population Distribution (Percent of WBC)
The share of total white blood cells that are lymphocytes, measured directly by NHANES (not derived from the absolute count).
Browse by Demographic
| Age (years) | male (1000 cells/uL) | female (1000 cells/uL) |
|---|---|---|
| 20-29 | 1.3–3.3 (2.2) | 1.4–3.8 (2.3) |
| 30-39 | 1.4–3.4 (2.3) | 1.3–3.6 (2.2) |
| 40-49 | 1.2–3.5 (2.1) | 1.1–3.5 (2.2) |
| 50-59 | 1.2–3.4 (2) | 1.2–3.6 (2.1) |
| 60-69 | 1.1–3.1 (1.9) | 0.9–3.4 (2) |
| 70+ | 0.9–3.2 (1.7) | 0.9–3.1 (1.8) |
Frequently Asked Questions
What do lymphocytes do?
Lymphocytes drive adaptive immunity. T cells coordinate and carry out targeted immune responses, B cells produce antibodies, and natural killer cells respond to infected or abnormal cells. The absolute count reflects the size of this circulating pool.
Why do lymphocyte counts change with age?
Thymic output declines and the balance of immune cell populations shifts across the lifespan, which gradually changes the circulating lymphocyte count at the population level.
Why are these population percentiles, not clinical reference ranges?
LabNorms shows where a value sits in the US adult population distribution. Clinical reference intervals are produced by laboratories using their own protocols and answer a different question. Both are useful and are not interchangeable.
What is a normal lymphocyte percentage?
Across US adult sex-and-age groups, the median lymphocyte percentage ranges from about 25.4% to 32.6% of total white cells. The share tends to fall with age. See the percent-of-WBC table for your group's full distribution.