warum bin ich immer müde — what does this mean exactly?

The question 'Why am I always tired?' has no single answer. Chronic fatigue is multifactorial: poor sleep, stress, diet, lack of exercise, or underlying conditions like hypothyroidism, iron deficiency, vitamin D deficiency, or insulin resistance. MyBody-X offers hormone and vitamin D tests that may flag low vitamin D (see context: Vitamin-D home test, evidence: marketing/mixed) or abnormal thyroid markers. However, these are screening tools, not diagnostic. The evidence in the provided context is weak to mixed; no direct fatigue studies are cited. DNA tests (e.g., SIRT1, TCF7L2) are not relevant for fatigue. Caveat: persistent tiredness requires a medical workup. Consumer test results can support a doctor's conversation but cannot replace clinical evaluation.