What do the blood tests mean?

An overview of what the different blood tests are about, what the normal values ​​are, and a little about what they mean. If you have had abnormalities, you can use this quick overview as a starting point to learn more about the answers you have received.

Hematology (blood cells)

Hemoglobin (Hb):

• Normal value: Men: 13,4–17,0 g/dL, Women: 11,7–15,3 g/dL
• Importance: Low Hb indicates anemia, high Hb may be due to dehydration or smoking.

Leukocytes (white blood cells):

• Normal value: 3,5–10,0 x 10⁹/L.
• Importance: High values ​​may indicate infection, low values ​​may be due to immune weakness.

Thrombocytes (platelets):

• Normal value: 145–390 x 10⁹/L.
• Importance: Low values ​​increase the risk of bleeding, high values ​​may indicate inflammation.

Hematocrit (Hct):

• Normal value: Men: 39–50%, Women: 34–46%.
• Importance: Low hematocrit may indicate anemia, high may be due to dehydration.

Electrolytes and fluid balance

Sodium (Na):

• Normal value: 137–145 mmol/L.
• Importance: Important for fluid balance and nerve function.

Potassium (K):

• Normal value: 3,5–5,0 mmol/L.
• Importance: Critical for muscle and heart function.

Calcium (Ca):

• Normal value: 2,15–2,51 mmol/L.
• Importance: Low levels may be due to vitamin D deficiency, high levels may indicate hyperparathyroidism.

Kidney function

Creatinine:

• Normal value: Men: 60–105 µmol/L, Women: 45–90 µmol/L.
• Importance: High levels indicate reduced kidney function.

eGFR (estimated glomerular filtration rate):

• Normal value: >90 ml/min/1,73 m².
• Importance: Low value indicates kidney failure.

Liver function

ALL:

• Normal value: <70 U/L.
• Importance: High levels may indicate liver damage.

ASAT:

• Normal value: <35 U/L.
• Importance: High levels may be due to liver damage or muscle damage.

Bilirubin:

• Normal value: <25 µmol/L.
• Importance: Increased levels can lead to jaundice.

Lipid profile (fats/cholesterol)

LDL (low-density lipoprotein):

• Normal value: <3,0 mmol/L.
• Particle size: Small, dense LDL are more atherogenic than large, airy LDL.

HDL (high-density lipoprotein):

• Normal value: >1,0 mmol/L (men), >1,3 mmol/L (women).
• Particle size: Large HDL particles protect against atherosclerosis.

Triglycerides:

• Normal value: <1,7 mmol/L.
• Particle size: Increased levels associated with small LDL particles.

ApoB (Apolipoprotein B):

• Normal value: <0,9g/L.
• Importance: Reflects the number of atherogenic particles (LDL, VLDL).

Blood sugar and diabetes

Glucose (fasting):

• Normal value: 4,0–6,0 mmol/L.
• Importance: High levels may indicate diabetes.

HbA1c:

• Normal value: <42 mmol/mol.
• Importance: Measures long-term blood sugar.

Metabolism

TSH (Thyroid stimulating hormone):

• Normal value: 0,5–3,6 mU/L.
• Importance: Indicates thyroid function.

Anti-TPO (Antibodies against thyroid peroxidase):

• Normal value: <35 IU/mL.
• Importance: Increased levels in autoimmune thyroiditis.

Autoimmune markers

ANA (Antinuclear antibodies):

• Normal value: Negative.
• Importance: Positive ANA may indicate lupus or other autoimmune diseases.

Anti-CCP (Antibodies to cyclic citrullinated peptide):

• Normal value: <7 U/mL.
• Importance: Specific for rheumatoid arthritis.

Heart health

Troponin:

• Normal value: <14 ng/L.
• Importance: Elevated in heart damage.

NT-proBNP (N-terminal pro-brain natriuretic peptide):

• Normal value: <125 pg/mL.
• Importance: Increased in heart failure.

Coagulation

INR (International Normalized Ratio):

• Normal value: 0,8-1,2.
• Importance: Monitors blood thinning treatment.

D-dimer (Breakdown product of blood clots):

• Normal value: <0,5 mg/L.
• Importance: Increased risk of blood clots.

Special tests for nutritional status

Homocysteine:

• Normal value: 5–15 µmol/L.
• Importance: Elevated levels may indicate a deficiency of folate, B6 or B12 and increase the risk of cardiovascular disease.

Transferrin saturation:

• Normal value: 20–50%.
• Importance: Shows how much iron is bound to the transport protein transferrin. Low values ​​may indicate iron deficiency.

Vitamin D (25-OH vitamin D):

• Normal value: >50 nmol/L (optimal: 75–150 nmol/L).
• Importance: Important for bone health, immune function and muscle strength. Low levels can lead to rickets or osteomalacia, while high levels (overdose) can lead to calcium deposits in tissues.

Vitamin B12 (cobalamin):

• Normal value: 170–650 pmol/L.
• Importance: Essential for red blood cell formation and nerve function. Deficiency can lead to pernicious anemia and neurological symptoms.

Folate (folic acid):

• Normal value: >7 nmol/L (varies somewhat between laboratories).
• Importance: Necessary for DNA synthesis and cell division. Deficiency can lead to megaloblastic anemia.

Vitamin A (retinol):

• Normal value: 1,0–3,0 µmol/L.
• Importance: Important for vision, immune function and skin health. Deficiency can lead to night blindness, while high levels can be toxic.

Vitamin E (alpha-tocopherol):

• Normal value: 12–42 µmol/L.
• Importance: An antioxidant that protects cells from damage. Deficiency is rare but can lead to neurological problems.

Vitamin K (coagulation vitamin):

• Normal value: Not routinely measured, but INR is used indirectly to assess coagulation.
• Importance: Important for blood clotting and bone health. Deficiency can lead to bleeding tendencies.

Iron:

• Normal value: 9–34 µmol/L.
• Importance: Important for oxygen transport in the blood. Low levels can lead to iron deficiency anemia, while high levels can be caused by hemochromatosis.

Ferritin:

• Normal value: Men: 20–300 µg/L, Women: 15–150 µg/L.
• Importance: Measures the body's iron stores. High values ​​may indicate inflammation or iron overload.

Zinc (Zn):

• Normal value: 11–18 µmol/L.
• Importance: Essential for the immune system, wound healing and DNA synthesis. Deficiency can lead to skin problems and a weakened immune system.

Selenium (Se):

• Normal value: 70–120 µg/L.
• Importance: Important for antioxidant function and the thyroid gland. Deficiency can lead to a reduced immune system.

Magnesium (Mg):

• Normal value: 0,7–1,0 mmol/L.
• Importance: Necessary for muscle function, nerve conduction and energy production. Deficiency can lead to cramps and heart problems.

Calcium (Ca):

• Normal value: 2,15–2,51 mmol/L.
• Importance: Important for bone health, muscle contraction, and nerve function. High levels may be due to hyperparathyroidism.

Phosphate (P):

• Normal value: 0,8–1,5 mmol/L.
• Importance: Important for bone health and energy production. Low levels may be due to vitamin D deficiency.

Copper (Cu):

• Normal value: 12–24 µmol/L.
• Importance: Important for the formation of red blood cells and enzymes. Low levels can lead to anemia, while high levels can indicate Wilson's disease.

Iodine:

• Normal value: Not routinely measured in blood, but can be measured in urine.
• Importance: Essential for thyroid hormones. Deficiency can lead to goiter.

Fluorine:

• Normal value: Not routinely measured.
• Importance: Overexposure can lead to fluorosis.

SOURCES

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