Is Transferrin useful for Müdigkeit?

Transferrin is an iron-transport protein commonly measured as part of iron status assessment. Iron deficiency anemia can cause fatigue, and in that state transferrin levels are often elevated (compensatory). However, transferrin alone is not a specific marker for fatigue – many other causes such as sleep deprivation, thyroid disorders, or chronic inflammation are more prevalent. Measuring transferrin can be useful within a complete iron panel (ferritin, serum iron, transferrin saturation) to detect iron deficiency anemia. The evidence linking iron deficiency to fatigue is strong (human-strong), but using transferrin as a standalone test for fatigue is not evidence-based. Caveat: normal transferrin does not rule out other fatigue causes. Persistent fatigue warrants a full medical workup.