What to watch with CYP1A2 and Müdigkeit?

CYP1A2 is key for caffeine metabolism. Slow metabolizers (e.g., *1F allele carriers) break down caffeine slowly, which can prolong alertness but also disrupt sleep, leading to daytime fatigue. Fast metabolizers may experience a shorter, more intense effect. However, fatigue is multifactorial: sleep quality, stress, nutrient status (iron, B12, vitamin D), and gut health usually matter more than a single gene. A DNA test can offer clues but does not replace medical evaluation for chronic tiredness. The evidence for direct actionable advice from CYP1A2 alone is weak – adjusting caffeine intake and timing is a pragmatic, low-risk step.