White Blood Cell Count (WBC)

Routine annual

also leukocyte count

What it isTotal count of all immune cells per microliter — neutrophils, lymphocytes, monocytes, eosinophils, basophils.

DoesDefends against pathogens, surveys for cancer, mediates inflammation and repair.

GoodA mid-low WBC count in a healthy person predicts the lowest all-cause mortality and reflects low chronic inflammation.

BadElevated WBC marks infection, inflammation, stress, or marrow disorders, and elevated baseline WBC predicts cardiovascular events. Very low WBC raises infection risk and can signal marrow failure or autoimmune disease.

Standard

3.4–10.8 K/µL.

Optimal

4.0–6.5 K/µL (narrow target)

Modifiers

Rises with stress, infection, smoking; falls with severe vitamin deficiency or marrow suppression.

How to optimize

Lifestyle: Quit smoking; address chronic inflammation; sleep 7–9 hours; resistance training.
Diet: Mediterranean pattern; cut ultra-processed food.
Supplements: Omega-3 EPA+DHA (2–4g/day), curcumin (500mg 2×/day), vitamin D3.
Peptides: Thymosin alpha-1, thymalin support immune balance.
Drugs: Treat underlying cause.

within Blood Cells