Can Nährstoffcheck help with fatigue?

A nutrient check can help with fatigue if a genuine deficiency is identified. Many people with fatigue have suboptimal levels of vitamin D, B12, iron, magnesium, or selenium. A blood test (e.g., MyBody-X) can detect such deficits. However, fatigue is multifactorial: sleep disorders, stress, hormonal imbalances (e.g., low testosterone), infections, or psychological factors often play a larger role. Evidence for standalone supplementation for fatigue without deficiency is weak. Moreover, DNA-based nutrient tests (e.g., on selenium gene variants) are mostly mechanistic and not sufficiently clinically validated. A nutrient check is useful as part of a medical workup, but not a magic bullet. Caveat: self-tests can give false reassurance; persistent fatigue warrants a doctor's visit.