TIBC
The optimal range for TIBC (Total Iron Binding Capacity) is commonly cited as 250–400 μg/dL, tighter than the standard lab reference range of 250–450 μg/dL. Transferrin capacity - elevated in iron deficiency, suppressed in iron overload.
How TIBC ranges relate
The standard lab range vs the optimization-focused target. Illustrative trajectory shows what a 12-week improvement pattern looks like — not real user data.
What TIBC Measures
TIBC measures transferrin's total binding capacity for iron. In iron deficiency, TIBC rises (more "empty seats" on the carrier) even before ferritin fully depletes. In iron overload (hemochromatosis), TIBC is suppressed.
Transferrin saturation (serum iron ÷ TIBC × 100) is the functional derived metric - optimal range is typically 25–45%.
What Affects This Biomarker
TIBC is influenced by: iron status (rises in deficiency, falls in overload), protein synthesis (low in liver disease or malnutrition), estrogen (raises it), and inflammation (suppresses it).
In the Context of Peptide Protocols
Reviewed as part of a full iron panel every 6–12 months when tracking iron. Persistent high saturation (>50%) warrants HFE gene workup for hemochromatosis.
Frequently Asked Questions
What does TIBC measure?
TIBC measures transferrin's total binding capacity for iron. In iron deficiency, TIBC rises (more "empty seats" on the carrier) even before ferritin fully depletes. In iron overload (hemochromatosis), TIBC is suppressed.
What is the optimal range for TIBC?
The optimal range for TIBC is commonly cited as 250–400 μg/dL. The standard lab reference range is 250–450 μg/dL.
What affects TIBC levels?
TIBC is influenced by: iron status (rises in deficiency, falls in overload), protein synthesis (low in liver disease or malnutrition), estrogen (raises it), and inflammation (suppresses it).
Where This Fits in Your Panel
TIBC is one marker on a fuller panel. The Peptide Blood Work Checklist lays out the complete baseline panel, what to add by protocol type, and when to retest.
See the full blood work checklist →Upload any lab PDF and MyProtocolStack maps your values to TIBC and 40+ other biomarkers. StackAI interprets the trend in context of your protocol.
Start tracking →Last reviewed: June 2026
Informational only - not medical advice. Reference ranges vary by lab and individual context. Work with a licensed provider to interpret your specific results.