Fasting Blood Sugar (FBS)
- Sample Type
- Standard
- Fasting
- No
- Unit
- mg/dL
Fasting Blood Sugar measures the circulating glucose in the blood after an 8 to 12-hour period of no caloric intake. Within the FBS & PPBS panel, it serves as the baseline for evaluating glucose homeostasis. It is the primary screening tool for diagnosing Diabetes Mellitus and Impaired Fasting Glucose (Prediabetes). It reflects the balance between hepatic glucose production and peripheral glucose uptake regulated by insulin.
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Enter your lab result to see where you stand compared to the standard reference range.
Why Context Matters
FBS can be elevated by 'stress hyperglycemia' (acute illness or pain), certain medications (thiazides, steroids), or poor fasting compliance. A single high reading is rarely sufficient for a diagnosis without a follow-up test or HbA1c correlation.
Lab ranges are statistical averages, not biological laws. "Normal" for a 20-year-old male isn't normal for a 60-year-old female.
Clinical References
Source-of-truth databases and clinical guidelines for Fasting Blood Sugar (FBS):
Official Sources
- Standards of Care in Diabetes | ADA Clinical Guidelinesprofessional.diabetes.org
- Diabetes Practice Guidelines & Resources | American Diabetes Associationprofessional.diabetes.org
- 2. Diagnosis and Classification of Diabetes: Standards of Care in Diabetes-2025 - PubMedpubmed.ncbi.nlm.nih.gov
Research & Guidelines
Related Indicators
Medically Reviewed by Dr. Binoy Babu, MBBS
Board Certified Doctor • 10+ Years Clinical Experience
Dr. Babu is a practicing physician dedicated to empowering patients with clear, actionable medical information. He founded 2opi to bridge the gap between complex lab reports and patient understanding, ensuring everyone has access to a reliable second opinion.
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