warum nehme ich trotz kaloriendefizit nicht ab — what are common causes?

The question of why weight loss stalls despite a calorie deficit is complex and not directly addressed in the provided context. Common causes include: metabolic adaptation (basal metabolic rate drops during prolonged deficit), water retention (due to salt, carbs, or hormonal fluctuations), inaccurate calorie tracking (portion sizes, hidden calories), reduced physical activity (muscle loss lowers energy expenditure), and medical factors such as hypothyroidism, insulin resistance, or medications. Stress and poor sleep can also raise cortisol, hindering fat loss. The provided knowledge (microbiome tests, allergy tests, Blue Zones) does not contain specific evidence or mechanisms for this issue. The evidence for these causes is mostly mechanistic or based on clinical practice, but not supported by the cited sources. A medical evaluation is recommended if weight loss plateaus persist.