warum nehme ich zu trotz kaloriendefizit — which blood markers matter?

Gaining weight despite a calorie deficit is a common frustration. It's rarely due to a single blood marker, but several can reveal underlying issues. Key markers include: **Thyroid panel** (TSH, fT3, fT4) – hypothyroidism lowers metabolic rate. **Fasting insulin and HOMA-IR** – insulin resistance can promote fat storage even with reduced calories. **HbA1c** – reflects long-term glucose control. **CRP** – chronic inflammation may impair metabolism. **Cortisol** – chronic stress promotes visceral fat. **Leptin** – resistance to this satiety hormone can disrupt energy balance. **Vitamin D** – deficiency is linked to weight gain. Important caveats: Calorie deficits are often overestimated (tracking errors, hidden calories). Water retention (sodium, menstrual cycle) can mask fat loss. These markers are not diagnostic; they provide clues. MyBody-X tests are screening tools, not medical devices. Always consult a doctor for interpretation. Evidence: strong for thyroid and insulin; moderate for inflammation and stress markers; mechanistic for leptin and vitamin D.