Unsaturated Iron Binding Capacity (UIBC)
- Sample Type
- Standard
- Fasting
- No
- Unit
- µg/dL
UIBC measures the reserve capacity of transferrin (the primary iron transport protein) that is not yet bound to iron. In an Iron Deficiency Profile, it is calculated by subtracting the serum iron from the Total Iron Binding Capacity (TIBC). It is a sensitive marker for iron status: as iron stores deplete, the body increases transferrin production, leading to a higher UIBC. Conversely, in iron overload states, the UIBC decreases as more binding sites are occupied.
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Enter your lab result to see where you stand compared to the standard reference range.
Why Context Matters
UIBC is highly dependent on serum iron levels, which exhibit significant diurnal variation (highest in the morning). Recent iron supplementation, oral contraceptives, or acute inflammation (which lowers serum iron) can provide a misleading picture of total body iron stores.
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 Unsaturated Iron Binding Capacity (UIBC):
Official Sources
Research & Guidelines
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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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