wie lange vor blutabnahme nichts trinken — which blood markers matter?

The question about fasting before a blood draw is valid because not all lab values are equally sensitive to fluid or food intake. General guideline: For most routine blood tests (e.g., fasting glucose, lipid panel), a fasting period of 8–12 hours is recommended, with moderate water intake allowed. However, sugary drinks, coffee with milk, or alcohol significantly distort results. Which markers matter? The MyBody-X Fitness | LifestyleCheck analyzes creatine kinase, cholesterol (HDL/LDL), blood sugar (HbA1c), calcium, vitamin B12, and vitamin D3. HbA1c reflects average blood sugar over 2–3 months and is not affected by short-term drinking. Fasting glucose, on the other hand, responds acutely to carbohydrate intake. Lipid values (HDL, LDL, triglycerides) require 9–12 hours of fasting because dietary fats interfere with measurement. Calcium and vitamin D3 are less fasting-dependent but can fluctuate with supplements or meals. Creatine kinase is influenced by physical activity, not by drinking. For cortisol (in the context of hormone profiling), the time of day is critical, not fasting. Important: Follow the specific instructions of your lab. When in doubt, moderate water is usually safe, but no other beverages. The evidence is based on clinical practice and laboratory standards.