When is APOE Alltag actually useful?

APOE genotyping (especially ε4) is often marketed for personalized lifestyle advice, but its practical utility in everyday life is limited. While ε4 is a well-established risk factor for late-onset Alzheimer's disease, there are no randomized controlled trials showing that knowing one's status leads to improved clinical outcomes. Some observational studies suggest potential interactions with dietary fat intake and cognitive activity, but effect sizes are small and not robust enough for individual recommendations. Furthermore, the knowledge of increased risk can cause psychological distress. APOE testing is only useful in daily life if conducted within a clinical context with family history of dementia and if the patient understands the predictive limitations. Without clear actionable steps, the benefit remains uncertain.