Fasting Blood Sugar (FBS)
FBS measures your blood glucose level after an 8–12 hour overnight fast. It is the primary screening test for diabetes and prediabetes. Elevated fasting glucose indicates impaired glucose metabolism and helps guide treatment decisions.
Test Information
Reports In
Same day (6 hours)
Parameters
1
Requisites
Blood Sample
Sample Type
Blood
Measures
Fasting plasma glucose level
Identifies
Diabetes, prediabetes, impaired fasting glucose
What is the FBS Test?
Fasting Blood Sugar (FBS) measures glucose levels in your blood after fasting for 8-12 hours. It's the most basic and widely used test for diagnosing diabetes and pre-diabetes. After fasting, your blood sugar should be below 100 mg/dL. A value between 100-125 indicates pre-diabetes, and 126+ on two separate occasions confirms diabetes.
Why Should You Take This Test?
FBS is the gold standard for diabetes screening. Early detection allows lifestyle changes and medication to prevent complications.
Who Should Get Tested?
Everyone Over 35
Annual screening recommended for all adults.
Family History of Diabetes
Risk is significantly higher if parents are diabetic.
Overweight Individuals
Obesity and insulin resistance go hand in hand.
PCOD Patients
Regular sugar monitoring due to insulin resistance.
Warning Signs — When Should You Get This Test?
Common Conditions Detected
Frequently Booked Together
Tests commonly ordered alongside FBS for a complete picture
HbA1c
3-month average blood sugar — more reliable than a single fasting reading
PPBS
Post-meal sugar to check how your body handles food
Fasting Insulin
Checks for insulin resistance
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