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

Gaining weight despite a calorie deficit is a complex issue that cannot be explained by DNA tests alone. Blood markers are often more informative. Key markers include: TSH, fT3, fT4 (thyroid function – hypothyroidism lowers basal metabolic rate), fasting insulin and HOMA index (insulin resistance promotes fat storage), cortisol (chronic stress increases visceral fat), leptin (leptin resistance impairs satiety), and inflammatory markers like hs-CRP. Vitamin D deficiency or gut microbiome imbalances can also affect metabolism. The genes mentioned in the context (FTO, MC4R) have only small effect sizes and do not explain significant weight gain under deficit. MyBody-X tests do not cover these genes. Conclusion: For unexplained weight gain despite a deficit, a physician should check the listed blood markers before relying on genetic tests. Evidence for blood markers is human-strong; for genetic markers it is weak.