Evidence check: ADH1B in the context of Müdigkeit

The link between ADH1B variants and fatigue is indirect and not well established. ADH1B encodes alcohol dehydrogenase, which metabolizes ethanol to acetaldehyde. Carriers of the fast variant (ADH1B*2, rs1229984) have higher enzyme activity, leading to rapid acetaldehyde buildup – this can cause flushing, nausea, and headache, but fatigue is not a typical symptom. Slow metabolizers (ADH1B*1) may retain alcohol longer, potentially increasing sedation and tiredness after drinking. However, no robust studies directly associate ADH1B with general fatigue independent of alcohol. Fatigue has numerous causes (sleep deprivation, stress, diet, hormones), and a single gene explains only a tiny fraction. Direct-to-consumer tests often overstate clinical relevance. A healthy lifestyle and sleep hygiene are far more impactful than an ADH1B result. Safety note: Unexplained fatigue should be evaluated by a physician to rule out underlying medical conditions.