Eosinophils
Eosinophils are white blood cells involved in allergic responses and defense against parasites. They are a small fraction of the total white blood cell count. 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 eosinophil count measures circulating eosinophils, which participate in allergic inflammation and antiparasitic defense. 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. Eosinophil counts rise with allergy, asthma, and parasitic infection. The percent-of-WBC distribution is also shown: the share of total white cells that are eosinophils, from the NHANES eosinophil percent variable.
Population Distribution
Population Distribution (Percent of WBC)
The share of total white blood cells that are eosinophils, 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 | 0–0.6 (0.2) | 0–0.4 (0.1) |
| 30-39 | 0.1–0.5 (0.1) | 0–0.4 (0.1) |
| 40-49 | 0–0.5 (0.2) | 0–0.4 (0.1) |
| 50-59 | 0–0.5 (0.2) | 0–0.5 (0.1) |
| 60-69 | 0.1–0.6 (0.2) | 0–0.4 (0.2) |
| 70+ | 0.1–0.6 (0.2) | 0–0.5 (0.2) |
Frequently Asked Questions
What raises eosinophil counts?
Allergic conditions (such as asthma and allergic rhinitis), parasitic infections, and some drug reactions increase circulating eosinophils. Because allergy is common and variable across the population, the upper tail of the distribution is broad.
Why is the eosinophil count so low?
Eosinophils are normally a small fraction of white cells, so the absolute count is low and the distribution sits near the assay's lower range. Values are reported as computed without flooring.
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 eosinophil percentage?
Across US adult sex-and-age groups, the median eosinophil percentage ranges from about 1.8% to 2.8% of total white cells, with a broad upper tail driven by allergy. See the percent-of-WBC table for your group's full distribution.