Albumin
Primary plasma protein for protein synthesis, liver function, and nutritional status
Also known as
Definition
Albumin is the most abundant plasma protein (approximately 55–60% of total proteins) and is produced exclusively in the liver. It performs central transport functions (fatty acids, hormones, medications, bilirubin, calcium), regulates colloid osmotic pressure, and is an important indicator of liver function, nutritional status, and protein deficiency. Albumin is a negative acute-phase reactant — it falls during inflammation.
| Parameter | Value |
|---|---|
| Unit | g/l |
| Reference Range | 35–52 g/l |
Agree on your personal target range with your doctor.
↓ What a low value means
Hypoalbuminemia (< 35 g/l) can indicate liver disease (reduced synthesis — important functional parameter in cirrhosis), malnutrition/protein deficiency, nephrotic syndrome (renal loss), chronic inflammation (negative acute-phase reactant), heart failure, or burns. Clinical consequence: edema (reduced oncotic pressure), impaired drug binding.
↑ What a high value means
Elevated albumin (> 52 g/l) is usually a sign of dehydration (concentration effect). Rarely: congenital bisalbuminemia. In dehydration: albumin normalizes rapidly after rehydration.
✓ What can influence this value
The albumin value is influenced by protein supply (malnutrition, cachexia), the synthesis capacity of the liver, protein loss through the kidneys or gut, inflammation, and fluid balance. Dehydration can make the value appear higher, and overhydration can make it appear lower. Body position during the blood draw and a long tourniquet time on the arm can also affect the measured result.
When to test
Routinely in liver function panels; nutritional screening (MUST score uses albumin); for edema, ascites, liver disease, kidney disease (nephrotic syndrome), chronic inflammation, and bariatric follow-up. Albumin as a long-term malnutrition marker (half-life ~20 days; prealbumin ~2 days is more sensitive for short-term changes).
Frequently asked questions
Why is albumin often low in chronic disease? +
In chronic inflammation, the body releases IL-6 and other cytokines. These signal the liver to reduce albumin production in favor of acute-phase proteins like CRP and fibrinogen. Low albumin in inflammation primarily reflects the inflammatory state, not protein deficiency.
How long does it take for albumin to respond to improved nutrition? +
Albumin has a half-life of approximately 20 days — it responds slowly to nutritional improvement. Prealbumin (transthyretin, half-life ~2 days) and retinol-binding protein (half-life ~12 h) are more sensitive markers for short-term nutritional improvements. Albumin remains relevant for long-term assessment.
What role does albumin play in interpreting calcium? +
About 40% of blood calcium is bound to albumin. With low albumin, total calcium appears falsely low even though active ionized calcium is normal. Formula: corrected calcium = measured calcium + 0.02 × (40 − albumin g/l). When albumin is abnormal, ionized calcium shows the active fraction directly.
Is albumin a marker of liver function or nutritional status? +
Both — depending on context. In liver disease (cirrhosis): albumin is a synthesis parameter and part of the Child-Pugh score for severity. In other conditions: albumin primarily reflects nutritional status and degree of inflammation. The value is only meaningful in the full clinical context alongside other lab values.
Albumin
Sources
Last updated: May 28, 2026
This information is for orientation only and does not replace medical advice. Reference ranges can vary by laboratory, method and country.