warum nehme ich trotz kaloriendefizit zu — when to see a doctor?

A true calorie deficit will eventually lead to weight loss – basic thermodynamics holds. Short-term weight gain despite a deficit is usually due to water retention (from salt, carbs, menstrual cycle), digestive contents, or hormonal shifts. Inaccurate tracking of calories or activity is also common. However, if weight persistently increases or plateaus over weeks despite a verified, consistent deficit, a doctor should be consulted. Potential medical causes include: hypothyroidism, insulin resistance, Cushing's syndrome, PCOS, medication side effects (e.g., antidepressants, corticosteroids), or chronic inflammation. Accompanying symptoms like fatigue, hair loss, cold intolerance, or unexplained edema are red flags. A physician can order blood work (thyroid panel, fasting insulin, cortisol) to identify underlying issues. Do not pursue extreme diets without medical supervision. The evidence for these recommendations is robust (physiological principles, clinical guidelines).