When your healthcare professional orders blood drawn for testing, and the physician instructs you to fast before the test, the first thing many people want to know is, can one drink water before blood test? This article will tell all the stories about blood test, and give you instructions to follow before a blood test.
Can You Drink Water Before a Blood Test?
Some people think they should avoid water before a blood test, not only is this untrue, it’s unhealthy. Yes, you can and it is better to do so, because:
It's important to keep hydrated during the fast, not only because it is healthy, it could also affect your triglyceride counts. These triglyceride countsare an important part when determining triglyceride levels in certain screenings. Dehydration increases the risk of artificially high readings of triglyceride levels, and drinking plenty of water will avoid this error.
What’s more, drinking water helps you feel better when you’re accepting the test. When the phlebotomist draws you blood, the more water you drink, the easier it is for him to locate your veins. And if urine tests are ordered along with blood tests, it will be easier for you to provide a sample.
However, you can only consume plain water, not soda, fruit drinks, sports drinks, coffee, or tea. Because the nutrients contained in them will affect the blood levels, and water is completely void of nutrients therefore will not interfere with the result of the test.
Tips to Help You Get Through the Blood Test
1. Know These Fasting Guides to Different Test
Can you drink water before a blood test?Generally speaking, you’ll want to follow your doctor’s orders when taking these different tests.
- Blood Glucose Test
Abstain from eating or drinking anything except water for at least 8 -10 hours before a blood glucose test. It is often the first test done to check for diabetes, a condition caused by too much sugar in the blood.
- Iron Blood Test
If your doctor suspects an iron deficiency, they may order a blood test taken in the morning before you eat anything. Avoid taking iron supplements for at least 24 hours before the blood draw. Iron is absorbed very quickly from food or pills, and can raise your iron levels affecting the test results.
- Blood Cholesterol Tests (lipid profile)
Physicians measure and diagnose cholesterol with a simple blood test, called a lipid profile. It's done after fasting, except water, for 9-12 hours to eliminate any contributing factors from any food you recently ate.
2. Tell the Doctor What Medications You're Taking
There are certain medications and substances that may alter the result of blood tests, and you may need to tell the doctor what medications you’re taking before your blood draw. Prescription medications including, over-the-counter medications, vitamins, alcohol, or recreational drugs, can affect the results of a blood test. Your health care provider will determine if you should wait 24-48 hours to have the blood work drawn, or if what you are taking will not significantly alter the blood test results.
3. Refrain from Certain Activities
There are some blood tests that are compromised by your activities. You may be asked to refrain from strenuous physical activity the day before a blood test, or you could also be asked to lie down and rest for a half hour before the blood test. Blood tests may be altered as a result of certain other activities such as smoking, herbal teas, or sexual activity. Be sure to discuss these activities with your physician prior to taking a blood test.
4. Warm Your Extremities
Before you take a blood test, you may be asked to warm the extremity where the blood will be drawn, using a warm compress over the area for 10-15 minutes to improve the blood flow. Remember also to wear warm clothes for the season before you go in to get your blood test. It will increase your skin temperature, increase the blood flow to the area, and make it easier for the phlebotomist to find a good vein.
5. Relax Yourself
No one likes getting a blood test, but the procedure is usually uneventful and brief. Many people are in and out of the lab in less than 15 minutes. If you feel quite nervous, chatting with your phlebotomist will help a lot to ease it. When your attention is distracted from the draw, the needle prick becomes a little less painful.
What Do the Results Tell?
1. Different Age Tells Different Result Meaning
Results can mean different things depending on your age. Normal levels of hemoglobin vary by age: it’s higher for adults and lower for children. Hemoglobin level of 11 to 13 grams/deciliter (gm/dl) for children is normal, a value of 13.5 to 15.5 gm/dl is normal for adults. Age makes a difference for your cholesterol numbers too, and most healthy people should have LDL cholesterol levels below 130 milligrams/dl, and levels greater than 160 pose a risk for heart disease fro man over 45 and women over 55.
2. ‘Positive’ May Not Be Positive
Some tests look for diseases by searching for markers in your blood, including the HIV test, sickle cell anemia test, hepatitis C test, and a gene test screening for breast and ovarian cancer risks. The results are considered positive when the blood test finds the marker, (DNA or protein), that is identified in the blood sample. In these cases, a positive test result means you may have the disorder or disease, or that you may have been exposed to it.
3. ‘Negative’ May Not Be Negative
A negative result means that the test did not detect what it was looking for, whether it was a disease marker or a risk factor for a specific health condition. When you have had a blood test to check for an infectious disease such as a test for hepatitis C, getting back a negative result is great news, because it means the blood test found no evidence of the infection.
4. Test Values Vary from Different Labs
Lab reports compare patient blood test results with a range that is considered normal for that laboratory. The lab’s range is referenced test results of many other people previously tested in the lab. This lab’s normal range may be different from another lab, so don’t be alarmed if you find out that a previous blood test report varied from the more recent report. After all, the differences could just be in the lab.