warum nehme ich nicht ab trotz kaloriendefizit und sport — what does this mean exactly?

The question means: 'Why am I not losing weight despite a calorie deficit and exercise?' – a common frustration. Possible reasons include: inaccurate calorie tracking (hidden calories, portion estimation errors), metabolic adaptation (the body lowers its basal metabolic rate during prolonged deficits), water retention (from muscle gain, salt, or hormones), insufficient protein or fiber, poor sleep, or high stress (cortisol promotes fat storage). Medical conditions like hypothyroidism or insulin resistance can also play a role. Genetic tests (e.g., FTO, PPARGC1A) offer clues but no definitive answers – effect sizes are small and overshadowed by lifestyle. Evidence for DNA-based weight loss recommendations is weak (marketing). Instead, focus on proven strategies: precise calorie and macronutrient tracking, resistance training to preserve muscle mass, adequate sleep, and stress management. Consult a doctor or dietitian if problems persist.