Myths about preparing for and taking tests
From the experience of the medical center I.D.Clinic
We would like to share some insights and dispel myths about the preparation and process of taking medical tests.
When scheduling various tests prescribed by a doctor, there is a lingering Soviet-era stereotype that nothing should be eaten or drunk beforehand. However, this is not entirely true.
Most tests can be taken without fasting.
But there are exceptions! You should not eat before taking tests for:
- diabetes;
- anemia;
- high cholesterol levels;
- liver diseases.
Why? Consider the diabetes test panel, blood glucose level.
When we eat or drink alcohol, the level of glucose, some minerals, vitamins, fat carriers (lipoproteins) and some enzymes in the blood changes. Measuring the level of these substances is crucial for diagnosing various diseases. If you eat food and sugary drinks, the glucose level will increase and the test will no longer be accurate
An alternative test for glucose levels that does not require fasting is the glycosylated hemoglobin test. It reflects the average blood sugar level over the past three months.
Iron is absorbed into the blood quite quickly. If we eat before the tests, they will show a falsely high result. Iron supplements should be stopped a day before donating blood.
The next test is for the level of cholesterol (triglycerides, high-density lipoproteins, low-density lipoproteins and very low-density lipoproteins).
After eating, the consumed fats are redistributed in the body, so the analysis will show an increased result. Also, before cholesterol level tests, you should not drink alcohol for a day – it can significantly increase the indicators.
There is an important clarification here: there are recommendations that allow you not to starve before taking a lipidogram (analysis of various fat carriers).
First of all, they concern:
- children
- elderly people
- people with diabetes
- people who are taking medication regularly
If you find it difficult to refrain from eating, for example, you experience severe discomfort if you do not eat, consult a doctor because everything has its consequences: additional costs for retaking the analysis, an incorrect diagnosis, incorrect treatment.
When studying markers of liver and kidney function, fasting and abstinence from alcohol are necessary
A vitamin B12 test measures how much vitamin is in the blood. This can help diagnose a specific type of anemia. Some medications can also distort the result, so it is worth discussing preparation for the test with your doctor.
When taking these tests: coffee, alcohol, smoking, medications, dietary supplements, hormonal drugs, chewing gum and exercise before donating blood distort the results.
In other cases, you can safely eat breakfast and not starve yourself before taking the tests.
What tests can you eat before?
- Blood count and hemoglobin level.
- Infectious disease tests and genetic tests.
- Glycosylated hemoglobin level (an additional marker of diabetes).
- Level of certain hormones in the blood.
Limit yourself to consuming fatty foods 24 hours before taking the tests – it is better to save a juicy burger or fried potatoes for lunch after visiting the laboratory.
If your test is on the list of those before which you need to refrain from eating for the time recommended by your doctor – do not postpone your visit to the laboratory for the middle of the day and schedule the tests in the morning.
This seems like simple advice, but many people find it difficult to follow it.
If you want to get the most accurate test results. Consult your doctor and follow his instructions.
Let’s draw conclusions! You don’t always need to starve before taking the tests!
You should always check with your doctor about the preparation for the tests that you have been prescribed.
You can always drink clean water regardless of the time of the appointment.
In most cases, you can not eat 2-4 hours before taking the tests.
But you don’t always need to take the tests in the morning!
I.D.Clinic reminds you that you can take all the tests in our medical center at a location convenient for you. Our doctors and nurses will provide all the necessary information for preparation and we wish you good health.