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Serum Free Fructosamine

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

This test measures a type of sugar protein in your blood that reflects your blood sugar levels over the past two to three weeks. It helps assess long-term glucose control, especially useful for people with diabetes.

Quick summary

["Helps track how well your blood sugar has been managed over time."]

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

Key facts at a glance

LOINC
47748-9
Short code
Serine SFr Spec
Synonyms
Serine SFr Spec
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

Why This Test Matters for Blood Sugar Control

Unlike immediate blood sugar checks, fructosamine gives a broader picture of your average glucose levels. It’s particularly useful for monitoring diabetes treatment effectiveness when daily blood sugar tests aren’t available.

How the Test Works

Your blood sample is tested to detect fructosamine, a form of sugar attached to proteins. The test measures this protein concentration, which reflects how your body has processed glucose over time.

What Normal Results Mean

While specific ranges vary by lab, higher fructosamine levels may indicate consistently elevated blood sugar, while lower levels could suggest better control. Your doctor will interpret results in the context of your overall health.

Common Reasons for Testing

Doctors may order this test to evaluate diabetes management, screen for undiagnosed high blood sugar, or monitor long-term glucose trends in people with chronic conditions like diabetes or prediabetes.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Fructosamine Level

Frequently asked questions

What causes fructosamine levels to change?
Fructosamine levels rise when blood sugar is consistently high (e.g., due to diabetes) or drops sharply (e.g., from severe illness or stress). Conversely, they may drop if blood sugar is well-controlled or if certain medications affect protein synthesis.
Does diet or exercise affect this test?
While diet and exercise influence daily blood sugar, fructosamine reflects *long-term* trends. Short-term changes (like a single meal or workout) won’t immediately alter your test result, but chronic lifestyle habits will.
Can fructosamine replace daily blood sugar tests?
No. Fructosamine is a complementary tool—it’s best used alongside daily glucose monitoring or HbA1c (another long-term test). Your doctor will decide which tests fit your needs based on your health goals.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 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