Where your DNA places you among other people, and the studies behind it.
Not tailored to your result, and not medical advice
Quit or Avoid Smoking: Of the modifiable factors studied, current smoking is the strongest known driver of a raised white cell count. Among 37,972 healthy Japanese adults, current smoking had the strongest association with an elevated WBC count of anything measured (odds ratio 6.60, 95% CI 5.43 to 8.02), and the effect appeared across neutrophils, lymphocytes, monocytes, eosinophils and basophils. In a longitudinal arm of 1,730 smokers, the 231 who quit saw both white cell and neutrophil counts fall significantly within one year (5.64 to 5.37 x 10^9/L) and stay lower for at least two more years, while those who kept smoking showed no change. Preventive Medicine Reports (PMC)
Carry Less Body Fat: White cell counts track with body fat more closely than with how much you sit or move. In 144 adults aged 40 to 65 who wore hip accelerometers for four consecutive weeks, BMI and waist circumference were positively correlated with WBC count (r = 0.28 and r = 0.25), sitting more was associated with a higher count and standing time with a lower one. Once BMI was added to the model most of the sitting and standing associations became nonsignificant, which suggests adiposity rather than activity pattern is doing most of the work. The study was small and cross-sectional, so it shows association, not cause. Int J Environ Res Public Health (PMC)
Eat a Mediterranean-Style Diet: In the Moli-sani study of 14,586 Italian adults, closer adherence to a Mediterranean dietary pattern was associated with lower leukocyte counts. Those scoring highest on the Italian Mediterranean Index had 1.41 times the odds of being in the lowest WBC-count group (95% CI 1.07 to 1.86). The authors reported that the antioxidant and dietary fiber content of the food modified this inverse association, which points at vegetables, fruit, legumes, whole grains and olive oil collectively rather than any single nutrient. The design is observational and cannot establish cause. Blood (PubMed)
Know Low Counts Can Be Normal: Much of the difference in white cell count between people is constitutional rather than behavioral, and no lifestyle change moves it. The Duffy-null genotype, common in people of African ancestry, lowers neutrophil counts without weakening immune defense. Among 120 healthy Black adults, median absolute neutrophil count was 2,820 cells per microlitre in Duffy-null participants against 5,005 in the others, and 23.8% of Duffy-null participants fell below 2,000 while none of the non-null group did. The authors note that the Duffy-null phenotype comes with normal bone marrow cellularity and a robust response to infection, and that among Black individuals biopsied for a low neutrophil count, 97% were Duffy-null and 97% of those had a normal biopsy result. Blood Advances (PMC)
Interpret One Reading With Caution: A white cell count is a moment in time, not a fixed characteristic. A clinical review notes that the peripheral white blood cell count can double within hours after stimuli such as surgery, exercise, trauma or emotional stress, and lists smoking, obesity, asplenia and chronic inflammatory conditions among the non-malignant causes of a raised count. A raised count is also a common sign of infection, particularly bacterial infection. The same review flags fever, weight loss, bruising and fatigue as symptoms that warrant medical assessment alongside a raised count. American Family Physician (PubMed)
How much of this is genetic?
Genetics explains 40% of why people differ in this trait. The rest is environment, daily habits and chance.
Heritability estimate: Astle et al. 2016, Cell
Background and further reading
White blood cells (leukocytes) are the cells of the immune system that defend the body against infection, and total white blood cell (WBC) count is one of the most routinely measured values on a complete blood count. It sums several cell types with distinct jobs: neutrophils and monocytes tackle bacteria and clean up debris, lymphocytes drive antibody and viral responses, and eosinophils and basophils handle parasites and allergic reactions. A typical adult count falls in a broad reference range of roughly 4,000 to 11,000 cells per microliter, and where a healthy person sits within that range is a fairly stable personal setpoint. This polygenic score reflects the inherited tendency toward a higher or lower baseline count, not a disease and not your count on any given day.
Genetic Basis: Where a person's baseline WBC count sits is partly heritable, with twin and population estimates placing the genetic contribution at roughly 40%. Large genome-wide studies of blood-cell traits have mapped hundreds of common variants that nudge counts up or down, most acting through blood-cell production and turnover in the bone marrow. The single most influential locus is ACKR1 (the Duffy blood group gene, also called DARC): a common regulatory variant, the Duffy-null allele, is associated with a lower neutrophil and total WBC count and is especially frequent in people of African ancestry. This is a benign inherited pattern rather than a sign of impaired immunity, which is one reason a genetically lower count is not, by itself, a concern.
Non-Genetic Factors: Day-to-day WBC count is highly responsive to the body's state, which is why a single reading is interpreted in context. Counts rise transiently with acute infection, inflammation, tissue injury, vigorous exercise, physical or emotional stress, and pregnancy, and cigarette smoking is a well-established cause of a persistently higher baseline. Counts can fall with certain viral infections, some medications and chemotherapy, and nutritional deficiencies. Corticosteroids characteristically raise the neutrophil count. Because of this sensitivity, a value outside the usual range is meaningful mainly when it persists and is considered alongside symptoms and other blood indices rather than in isolation.
The published research behind your score, and the variants it draws on.
20 published scores from 9 studies
The WBC count score combines 20 polygenic scores drawn from 9 published studies.
These traits are influenced by some of the same genes and variants as this one
Platelet Count: The number of platelets, the clotting cell fragments, per volume of blood.
Hemoglobin: The oxygen-carrying protein in red blood cells, measured on a routine blood count.
Crohn's Disease: Chronic inflammatory bowel disease affecting the digestive tract lining.
Content updated August 2026.
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