Most Common Blood Tests (And What They’re Used For)

Medical professionals administer a wide variety of blood tests to diagnose for numerous health concerns—from general issues like anemia and electrolyte deficiency to serious health issues like kidney disease and diabetes.

Here are the ten most common blood tests and their uses…

1. FBC

A full blood count (or FBC) test is taken for most general health screenings—such as anemia, internal bleeding, poor diet, low white blood cells (which could indicate viral infections or bone marrow issues), high white blood cells (could indicate leukaemia), autoimmune conditions, or inflammation. It’s taken via a small sample of blood from a vein, typically in the arm.

2. Blood Glucose

Commonly referred to as a blood sugar test, this sample is taken to diagnose and monitor diabetes patients, or more specifically, high levels of glucose, which can lead to kidney disease or nerve damage. It’s taken via a tiny “pin prick” in the finger and can be done by the patient at home.

3. Electrolyte Blood Test

This test measures the concentration of electrolyte (or mineral) balance in your bloodstream to help indicate issues like dehydration or diabetes (due to increased sodium); kidney failure (due to low sodium).

4. Gene test

This test is used to find gene mutations in cases of suspected haemophilia, polycystic kidney disease, cystic fibrosis, sickle cell anaemia and other gene mutation issues. It’s taken via a small sample of DNA via the blood.

5.  Erythrocyte Sedimentation Rate

An erythrocyte sedimentation rate (or ESR) blood test screens for inflammation issues, such as arthritis, and Crohn’s disease. It typically monitors how fast the red blood cells in the sample fall to the bottom of a test tube—more quickly indicates inflammation.


The long-winded enzyme-linked immunosorbent assay (or ELISA) tests for food allergies (i.e., peanut allergies), HIV, or viral-bacterial issues. It takes a small blood sample and measures for specific antibodies related to the infection or allergy.

7. Blood Cholesterol

A blood cholesterol test measures a small blood sample (following a short 12-hour fast) for fatty lipids, or the substance produced by the liver from fatty foods. An abundance of lipids can result in cardiovascular disease, like heart attack or stroke.

8. Chromosome testing

Karyotyping, or chromosome testing, examines individual blood cell chromosomes under a powerful microscope when physical or developmental disabilities or infertility is suspected.

9. Blood culture

A blood culture examines the blood for bacterial infections of the blood that may cause Septicaemia (or septic shock). This tests demands 2 blood samples (for accuracy)—typically one from the arm and another from the leg—to test for traces of bacteria in your blood.

10. Blood Typing

A blood-typing test is typically taken before a blood transfusion to identify patient blood grouping (for blood type matching). Otherwise, the risk of the immune system attacking the patient’s red blood cells may occur (i.e., rhesus disease).



Emily Lockhart

Emily Lockhart is a certified yoga instructor and personal trainer. She believes that being healthy is a lifestyle choice, not a punishment or temporary fix to attain a desired fitness or body image goal. Anna helps her clients take responsibility for their own health and wellness through her classes and articles on ActiveBeat.