Myths vs facts: CYP1A2 and Schlaf

CYP1A2 is the primary enzyme metabolizing caffeine. A common myth is that your genetic variant alone determines whether coffee ruins your sleep. Fact: Slow metabolizers (e.g., *1F carriers) clear caffeine more slowly, which can reduce sleep quality – especially if caffeine is consumed later in the day. Fast metabolizers may tolerate coffee better, but dose, timing, tolerance, and sleep hygiene are equally or more important. The gene's effect size is moderate; lifestyle factors dominate. A DNA test cannot diagnose sleep disorders. For better sleep, focus on limiting caffeine after noon, consistent bedtimes, and stress reduction. Evidence: human-moderate (caffeine metabolism well-studied, sleep link indirect).