Albumin
Also known as: Alb
What Does Albumin Measure?
Albumin is the most abundant protein in the blood, produced by the liver, and this test measures its concentration in the bloodstream. It plays a critical role in maintaining oncotic pressure — the force that keeps fluid within blood vessels — and acts as a transport protein, carrying hormones, fatty acids, medications, calcium, and other substances throughout the body. The albumin blood test reflects how well the liver is synthesizing proteins and provides a snapshot of overall nutritional status.
Why Does Albumin Matter?
Albumin levels are a powerful indicator of liver function, kidney health, and nutritional adequacy. Low albumin (hypoalbuminemia) is associated with increased risk of complications, longer hospital stays, and higher mortality in both acute and chronic illness. It is routinely used to monitor patients with liver disease, kidney disease, malnutrition, and inflammatory conditions. Because albumin has a relatively long half-life of about 20 days, it reflects protein status over weeks rather than days, making it a reliable marker for chronic nutritional and hepatic assessment.
Normal Ranges
Males
3.5–5.0 g/dL
Females
3.5–5.0 g/dL
Children
3.8–5.4 g/dL (varies by age; slightly higher in infants and young children)
Causes of High Levels
- Dehydration or hemoconcentration (relative elevation due to reduced plasma water)
- High-protein diet in the context of fluid loss
- Use of anabolic steroids or certain hormones
- Prolonged use of a tourniquet during blood draw (artifactual elevation)
- Excessive intravenous albumin infusion
Causes of Low Levels
- Liver disease (cirrhosis, hepatitis) impairing albumin synthesis
- Malnutrition or protein-deficient diet reducing substrate for production
- Nephrotic syndrome causing excessive albumin loss through the kidneys
- Chronic inflammatory conditions (sepsis, rheumatoid arthritis, Crohn's disease) increasing catabolism
How to Improve Your Albumin
Diet
- Increase high-quality protein intake to 1.2–1.5 g/kg body weight per day using lean meats, poultry, fish, and eggs
- Include dairy products such as Greek yogurt, cottage cheese, and milk which provide complete proteins and support albumin synthesis
- Add plant-based proteins like legumes, tofu, tempeh, and quinoa to diversify amino acid intake
- Consume adequate calories (energy) to prevent protein being used as fuel rather than for synthesis
- Eat small, frequent protein-rich meals throughout the day to maximize anabolic stimulation
Supplements
- Whey protein powder (20–40 g/day) as a highly bioavailable complete protein source to support hepatic albumin production
- Essential amino acid (EAA) supplements (10–15 g/day) particularly useful for those with poor appetite or absorption issues
- Vitamin D (1,000–2,000 IU/day) as deficiency is common in liver disease and may impair protein synthesis
- Zinc (8–15 mg/day) which supports liver protein synthesis and is frequently deficient in liver disease
- Branched-chain amino acids (BCAAs, 5–10 g/day) which can support albumin synthesis in patients with chronic liver disease
Related Biomarkers
Frequently Asked Questions
What does it mean if my albumin is low?
Low albumin (below 3.5 g/dL) can indicate liver disease, malnutrition, kidney problems, or a chronic inflammatory condition. It is rarely caused by diet alone in otherwise healthy people. Your doctor will typically look at your other lab values and symptoms to determine the underlying cause. In hospitalized patients, low albumin is considered a marker of poor prognosis and nutritional risk.
Can I raise my albumin levels by eating more protein?
Increasing dietary protein intake can help raise albumin levels when low albumin is caused by malnutrition or inadequate protein intake. However, if the cause is liver disease, kidney disease, or chronic inflammation, dietary changes alone may not normalize levels until the underlying condition is treated. Aim for 1.2–1.5 grams of protein per kilogram of body weight daily from high-quality sources like eggs, fish, poultry, and dairy.
Is albumin the same as the protein in urine?
No, though they are the same molecule. A blood albumin test measures albumin in your bloodstream, while a urine albumin test (microalbuminuria or albuminuria) measures how much albumin is leaking into your urine. Healthy kidneys should retain albumin in the blood; detecting it in urine signals that the kidneys may be damaged, which is an early warning sign of diabetic kidney disease or other kidney conditions.
How is albumin used to calculate corrected calcium?
About 40–50% of calcium in the blood is bound to albumin for transport. When albumin is low, total calcium levels appear falsely low even if the physiologically active (ionized) calcium is normal. A corrected calcium formula adjusts for this: Corrected Calcium = Measured Calcium + 0.8 × (4.0 − Albumin level). This calculation helps doctors avoid misdiagnosing hypocalcemia in patients with low albumin.