What Are Blood Tests Used For?

Blood tests are common medical tests used by healthcare providers to diagnose medical conditions, assess overall health, monitor chronic conditions, or see how well a medication or treatment is working.
Normal ranges for blood test results may include:
- Liver enzymes
- Different liver enzymes are tested to determine cellular dysfunction versus cellular damage versus liver obstruction
- ALT (alanine aminotransferase) Female 7-30 units/L; Male 10-55 units/L
- Alkaline phosphatase Female 30-100 units/L; Male 45-115 units/L
- AST (aspartate aminotransferase) Female 9-25 units/L; Male 10-40 units/L
- Bilirubin – total 0.0-1.0 mg/dL
- Gamma glutamyl transferase (GGT) Female 45 U/L; Male 65 U/L
- Lactate dehydrogenase (LDH) (total) 270 U/L
- Different liver enzymes are tested to determine cellular dysfunction versus cellular damage versus liver obstruction
- Electrolytes
- Important electrolytes are checked because each has a function on different cellular processes in the body
- Calcium 8.5-10.5 mg/dL
- CO2 (bicarbonate) 20-32 mmol/L
- Chloride 95-108 mmol/L
- Phosphorus 2.5-4.5 mg/dL
- Potassium 3.4-5.0 mmol/L
- Sodium 135-145 mmol/liter
- Important electrolytes are checked because each has a function on different cellular processes in the body
- Hormones
- To check for glandular dysfunction in the body
- Cortisol 0-25 µg/dL (depends on time of day)
- Stress hormone
- Estradiol Female premenopausal 30 to 400 pg/mL; Female postmenopausal 0 to 30 pg/mL; Male 10 to 50 pg/mL
- Female sex hormone
- Testosterone, total Female 6-86 ng/dL; Male 270-1070 ng/dL
- Male sex hormone
- Cortisol 0-25 µg/dL (depends on time of day)
- To check for glandular dysfunction in the body
- Blood components
- To check levels of these elements within the blood
- Albumin 3.1 – 4.3 g/dL
- Non-cellular component of blood plasma
- Platelets (thrombocytes) 130-400 x 103/µL
- Blood component that helps blood coagulate
- Red blood cell count (RBC) Female 3.9-5.2 x 106/µL; Male 4.4–5.8 x 106/µL
- Blood component that carries oxygen
- Hematocrit Female 36.0-46.0% of red blood cells; Male 37.0-49.0% of red blood cells
- Hemoglobin Female 12.1 to 15.1 g/dL; Male 13.8 to 17.2 grams per deciliter (g/dL)
- WBC (white blood cells, leukocytes) 4.5-11.0 x 103/mm3
- Blood component that helps fight infection
- Eosinophils 0-8% of white blood cells
- Lymphocytes 16-46% of white blood cells
- Basophils 0-3% of lymphocytes
- Monocytes 4-11% of white blood cells
- Neutrophils 45-75% of white blood cells
What Other Types of Blood Tests Are Used?
Other common tests healthcare providers may use to assess a person's general health may include the following:
- Amylase 53-123 units/L
- Pancreatic enzyme
- Blood urea nitrogen (BUN) 8-25 mg/dL
- Kidney function test
- Cholesterol, total less than 200 mg/dL
- Erythrocyte sedimentation rate (sed rate) Female 30 mm/h; Male 20 mm/h
- Inflammatory marker
- Glucose, plasma 70-110 mg/dL
- Lactic acid 0.5-2.2 mmol/L
- An acid by-product of cellular energy use; a marker for severe illness or sepsis
- Triglycerides 40-150 mg/dL
- A fatty substance in the blood
From 
References
REFERENCES:
Image source: iStock Images
https://www.iapac.org/fact-sheet/normal-laboratory-values/
https://www.mountsinai.org/health-library/tests/hemoglobin
https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=167&ContentID=estradiol
https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/blood-test
Image source: iStock Images
https://www.iapac.org/fact-sheet/normal-laboratory-values/
https://www.mountsinai.org/health-library/tests/hemoglobin
https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=167&ContentID=estradiol
https://www.hopkinsmedicine.org/health/treatment-tests-and-therapies/blood-test