Did your doctor instruct you to fast before your blood test? Are you thinking of eating just a little something to silent your ever-demanding stomach? After all, just a bite or two doesn’t seem to be a crime. Behold! Don’t think of breaking your fasting before your physical examination.
Fasting may not be necessary for all of your tests; however, it’s crucial and influences a few tests’ accuracies. Even a simple slip to temptation may lead to an incorrect result. Join me to know more about fasting, which tests require fasting, and 7 vital importance of fasting before a physical exam.
What is Fasting?
Fasting before a physical exam means you can’t eat or drink anything but water before a physical examination, usually for 8 to 12 hours. For example, if you have an appointment at 8 a.m. for your medical tests and you have to fast for 8 hours, it’s better not to eat anything except water after midnight.
Not only that, you should not smoke, chew gum, drink tea, coffee, anything. Even exercise often joins the fasting requirements as it may affect your digestion, and thus your result. In case of your regular prescription medication at night or in the morning, you can take them unless your doctor tells you not to. However, it’s always advisable to inform your doctor about your medications.
Which Tests Need Fasting?
Medical examinations are essential to detect your conditions and issues. Based on your test results, doctors determine their procedure, your medication, and the further necessity of other tests. However, is fasting before physical exams necessary all the time? Or, what is the importance of fasting before a physical exam?
Not all medical tests require fasting. However, there are some tests where fasting is essential as they help determine the accurate result, especially blood tests. Usually, you need fasting before the following tests-
- Glucose tests
- Lipid profile
- Basic or comprehensive metabolic panel
- Vitamin B12 test
- Iron test
- Gamma-glutamyltransferase or GGT enzyme
7 Vital Importance of Fasting Before a Physical Exam
For the correct diagnosis of your condition, you must fast as instructed by your doctor. The reason being, when you eat food or drink tea, coffee, or alcohol, they break down in your stomach and are absorbed into your bloodstream. It can influence certain substances in your blood, causing a rise in levels.
Conclusion: an inaccurate result and then a wrong diagnosis. Now, this is not something you would prefer. Therefore, what can you do? Unmistakably follow your doctor’s instructions, and fast before your medical tests. Let’s see 7 vital importance of fasting before a physical exam.
Diabetes and Glucose Guide
Fasting before blood tests is highly crucial while measuring the amount of glucose to test for diabetes and prediabetes in your blood. Fasting blood glucose checks the sugar level to see if the amount is healthy or unhealthy. If you have diabetes, your result will show an increased level of sugar in your blood.
Fasting in a fasting blood glucose test helps to determine the accurate sugar level in your blood. Depending on the record and result, your doctor can diagnose diabetes. Therefore, it’s wise not to eat or drink for 8 to 10 hours before a fasting blood glucose test if you want an accurate result. However, you can drink water only.
Lipid Profile Lookout
The lipid profile checks the cholesterol level in your blood. Cholesterol is a fatty substance that travels throughout your body in your blood. Cholesterol plays a significant role in your body – making cell membrane and cell structure, producing sex hormones, bile production in the liver, etc.
However, a high cholesterol level may cause several severe health issues, especially heart attack and stroke due to the fatty deposit in your blood vessels. Doctors usually suggest a lipid profile to check the status of cholesterol in your body that includes-
- HDL cholesterol or good cholesterol
- LDL cholesterol or bad cholesterol
Therefore, it is essential to fast before your test as your recently consumed food may increase the fatty substance in the blood. Thus, you will not get an accurate result of your cholesterol levels. However, a recent study suggested that not all tests to check cholesterol levels require fasting. A non-fasting test depends on your doctor’s diagnosis procedure and decision or if you are younger than 25 years. However, alcohol is strictly prohibited for at least 24 hours before a lipid profile as it may increase the cholesterol level in your body.
An iron blood test checks the iron level in your blood – too low or too high. Iron deficiency, aka, anemia is a significant problem that may cause many severe health conditions. However, eating food before the iron blood test may result in an inflated iron level because many foods contain iron which absorbs pretty quickly from food to your blood. Therefore, doctors prescribe you not to eat anything on the morning of the test to ensure an accurate result.
Vital for Vitamin B12
Vitamin B12 is an essential nutrient that keeps your nerve cells healthy, makes DNA, and makes red blood cells, transporting oxygen throughout your body. Due to vitamin B12 deficiency, you experience severe fatigue and weakness.
Vitamin B12 test usually measures the amount of vitamin B12 in your blood. However, you can take this test anytime after consuming food; your doctor may instruct you to fast for 6 to 8 hours before the test as the food may interfere with the test. Fasting ensures the accuracy of the vitamin levels in your body.
Liver Disease Determiner
Gamma-glutamyl transferase checks the GGT enzyme level in your system that helps to diagnose liver disease. If your result shows a high level of GGT in your body, it indicates liver disease, bile duct problems, or alcohol abuse in your body.
Your doctor may suggest you fast for at least 8 hours before the test to get an accurate answer as substances from food may interfere with your result. However, you must avoid drinking alcohol and smoking for 24 hours before the test as they can affect your GGT levels. Therefore, if you want to ensure your liver’s correct result and diagnosis, listen to your doctor and fast.
Gastroscopy and Colonoscopy Accuracy
A gastroscopy, an examination of the stomach, can help detect gastritis or peptic ulcers. In the test, your caregiver uses a gastroscopy instrument to look inside your food pipe, stomach, and the first part of the intestine.
You must fast before this test to decrease the risk of vomiting up and inhaling the substance in your stomach. Neither you can eat foods nor drink for 6 hours before a gastroscopy to get a clear view inside your stomach and intestine. On the other hand, a colonoscopy helps check the large intestine and rectum abnormalities. A doctor inserts a long thin, flexible tube with a camera on top into your rectum.
A colonoscopy requires a long preparation and fasting. Usually, before the test, you have to eat a low-fiber diet for 1 to 2 days. Next, the day before the test, you can have clear fluids like tea, coffee, and juice. To have a clear and empty bowel, you may need to fast for several hours and take bowel preparation medications.
Checking Your Comprehensive Metabolic Panel
A comprehensive metabolic panel is a routine physical examination that checks your blood sugar, electrolyte, fluid balance, and kidney and liver function. Your typical fasting time is 10-12 hours before the test.
Accuracy in the physical examination is crucial to diagnose your health issue. However, do all the tests require fasting? Can I eat or drink before having a blood test? What is the importance of fasting before a physical exam? No, not all physical tests require fasting. However, there are few tests that, without fasting, may not be accurate and thus an incorrect diagnosis. Here are 7 vital importance of fasting before a physical exam.
MyConciergeMD, is a perfect health center for you where the expert staff and technicians perform an ideal test providing an accurate result. Contact Dr. David Nazarian to get the best test detection and diagnosis of your health issues.