warum bin ich immer müde — which blood markers matter?

Chronic fatigue is multifactorial and cannot be reduced to single gene variants. The provided context does not contain specific blood markers for fatigue. Clinically established blood markers to investigate fatigue include: iron status (ferritin, transferrin saturation), vitamin B12, folate, vitamin D, thyroid function (TSH, fT3, fT4), complete blood count (hemoglobin, MCV), and inflammatory markers (CRP). An oral glucose tolerance test may be considered if insulin resistance is suspected. The gene variants mentioned in your context (ACE rs4341, APOA5 rs662799, FUT2, ADH1B, SIRT1, MMP1, CYP2D6) have no direct, validated link to fatigue. For instance, rs662799 is associated with higher triglycerides but not with exhaustion. The evidence for these genes is mechanistic or population-based, not applicable to fatigue symptoms. Seek medical advice; do not self-diagnose based solely on genetic tests. A standard blood panel from your primary care physician is the appropriate first step.