Total Protein in Serum

Published: August 9, 2026Updated: August 16, 2026

This test measures the total amount of protein in your blood serum, which includes both albumin and globulin proteins essential for maintaining fluid balance and supporting immune function.

Quick summary

["Your blood protein levels help assess overall health and detect potential issues like dehydration, liver disease, or kidney problems."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC: 11219-3
Short code: SFLC
Synonyms: BJ Protein Ser Ql
Category: chemistry
Sample: serum
Container: Serum separator tube (SST, gold top) or red-top tube
Units: N/A
Ref low: 3.3
Ref high: 19.4
Fasting: false
Population: adult
Sex: all
Age range: 18–65 years
Method: Immunonephelometry
CPT: 83520
SNOMED: 104931001
Specimen volume: 1-2 mL of serum
Stability: Stable for 7 days at 2-8°C; for longer storage, freeze at -20°C or below
Hemolysis max: 500
Lipemia max: 1000
Icterus max: 500
TAT: 24–72 hours
Order: routine

Why This Test Matters

Blood protein levels are vital for many bodily functions, including transporting nutrients, maintaining blood pressure, and supporting the immune system. Abnormal levels may signal underlying health concerns that need further evaluation.

What to Expect Before the Test

No special preparation is needed, but avoid heavy meals 2–3 hours before your blood draw. Stay hydrated unless your doctor advises otherwise.

Common Causes of Abnormal Results

Low protein levels might indicate conditions like malnutrition, liver disease, or kidney problems, while high levels could suggest dehydration, inflammation, or certain cancers.

How Results Are Interpreted

Your doctor will compare your results to standard ranges and consider your medical history, symptoms, and other tests to determine if further action is needed.

Reference range

Kappa free light chains: 3.3-19.4 mg/L; Lambda free light chains: 5.7-26.3 mg/L; Kappa/Lambda ratio: 0.26-1.65N/A

Specimen: serum

No special preparation required. Fasting is not necessary.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical Significance

Short name

Total Protein

Frequently asked questions

What might cause my protein levels to be too high or too low?

High protein levels can result from dehydration, severe infections, or conditions like multiple myeloma. Low levels may signal liver disease, kidney dysfunction, or malabsorption issues. Always discuss your results with your healthcare provider.

Do protein levels change with diet?

Yes, diet can influence protein levels. High-protein diets may temporarily raise levels, while deficiencies in certain nutrients (like protein itself) can lower them. Your doctor may recommend dietary adjustments if needed.

Is this test painful or uncomfortable?

The blood draw itself is brief and typically causes mild discomfort. Most people experience only a small pinch at the injection site, which usually fades quickly. Local numbing cream may be applied beforehand.

Sources

1
MedlinePlus — Laboratory TestsSource
2
Lab Tests OnlineSource
3
Mayo Clinic — Tests & ProceduresSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy