Unsaturated iron binding capacity (UIBC) represents the portion of iron binding sites on transferrin that are not occupied by iron. UIBC is often measured along with iron and total iron-binding capacity (TIBC) as a diagnostic tool to determine various iron disorders.
What might a low result mean?
A low UIBC indicates that you may have too much iron in your blood which may be due to iron overload syndrome (hereditary haemochromatosis). A low UIBC means that a large proportion of the binding sites on transferrin are saturated with iron.
What might a high result mean?
A high UIBC signifies iron deficiency as it means that a large proportion of the binding sites are not saturated with iron. Iron deficiency could be due to low dietary intake of iron, blood loss (including gastrointestinal bleeding and menstruation) or pregnancy.