Though several tests might be accurate when drinking coffee before the test, the fasting blood sugar test will not be. FBS or fasting blood sugar, measures the amount of glucose in the blood. This is actually used when you are being examined for diabetes or other ailments..Therefore, avoid drinking coffee during the fasting period, especially if you are expecting a very accurate blood test result that is important if you are suspected from a heart disease or cardiovascular issue. Having high triglycerides level also makes coffee absence for hours before the test significant..Can I have black coffee before a fasting blood test Is it ok to drink black coffee when your fasting for blood test? Fasting for Labs. Yes. There are no sugar or .Can I have coffee before a fasting blood test Is it ok to drink black coffee when your fasting for blood test? Fasting for Labs. Yes. There are no sugar or fat .
Preparing for Your Test. A fasting blood test requires that you avoid eating or drinking anything except water for a certain period of time before your blood test..Preparing for Your Test. A fasting glucose test measures the level of glucose in your blood during a fasted state. This type of test requires that you avoid food and .