Is Your Blood Glucose Screening Accurate?

Is Your Blood Glucose Screening Accurate?

Twenty-nine million Americans have diabetes, according to the CDC. Before the advent of insulin and other diabetes therapies, a diabetes diagnosis could very well be a death sentence. Today, people live long and fulfilling lives with this condition, but not without proper treatment. The earlier your diabetes is detected, the better your chances will be for returning to optimum health. A blood glucose screening is the simplest way to test you for this condition, as well as assess your future risk. But the test isn't perfect, and what you do in the days leading up to the test could alter the results.

1. Forgetting to fast

Your blood glucose screening will only work if you fast for the time your doctor requests—usually 12 hours. Otherwise, your blood sugar may spike, creating a false positive. Do not have any food, and limit yourself only to water, since soda, juices, and even tea often contain high levels of sugar.

2. Changing your diet

A sudden change in your diet can temporarily alter your blood glucose, even when you fast immediately before the test. In the days leading up to the test, don't try to fool the test by switching to a healthy diet. Instead, continue eating as usual, since this will give the most accurate reading of how your body manages glucose from day to day. You should also avoid celebratory meals and excessive drinking, since eating a giant birthday cake or consuming lots of alcohol can both spike your glucose numbers.

3. Drugs and alcohol

Drugs and alcohol change how your body reacts to glucose. If you have a drug or alcohol habit, be sure to tell your doctor. You should also avoid recreational drugs before your test, and if you take prescription drugs, give your doctor a comprehensive list. Even drugs not designed to control glucose can alter the test results.

4. Insulin therapy

If you are already on insulin therapy, your blood sugar might be well-controlled, even though your body cannot do the work on its own. Tell your doctor about your history with insulin therapy. If you take drugs, such as Metformin, to control pre-diabetes, ensure your doctor knows.

5. Excessive hydration

Many websites advise readers to drink lots of water before a blood test. After all, it makes the veins easier to find, and can help you cope with fasting-induced hunger. A few glasses of water—and even the recommended eight glasses—will not change the test results. But if you get nervous about the test and down gallons of water, this could dilute your blood sugar, causing a false negative.