If you're scheduled for a fasting blood test, you might be wondering: Can I drink coffee beforehand? It's a common question with an answer that could affect the accuracy of your results. Let's break it down so you're fully prepared. What Is a Fasting Blood Test? A fasting blood test is a diagnostic tool used to measure various health markers in your blood, such as: Blood glucose (for diabetes screening) Cholesterol and lipid levels Triglycerides Basic metabolic panel (BMP) Liver function tests For accurate readings, your doctor may instruct you to fast for 8–12 hours before your blood is drawn. This means no eating or drinking anything except water during that window. Can You Drink Coffee Before a Fasting Blood Test? Short Answer: No, you should not drink coffee before a fasting blood test. Even if you take it black—without sugar, cream, or milk— coffee can still affect your blood test results. Here’s why: Why Coffee Affects Blood Test Re...