What we usually call fasting blood sugar refers to blood sugar after fasting for 8 to 12 hours, that is, blood sugar in the fasting state in the morning. Blood sugar before lunch and dinner are not included in this list. It is best to measure fasting blood sugar between 6:00 and 8:00 in the morning. Do not use anti-diabetic drugs, do not eat breakfast, and do not exercise before the test. This can eliminate some influencing factors to a large extent and reflect the true condition.
However, we often find in clinical practice that the fasting blood glucose results of some patients are unreal and do not reflect the true blood sugar situation, including patients who monitor themselves at home or go to the hospital for blood testing. It’s important to know what factors can cause unrealistic fasting blood glucose results.
1. Dietary factors: Eating a large amount of food that is difficult to digest at night, or having dinner too late (too late will lead to a fasting time of less than 8 hours) may lead to high fasting blood sugar levels the next morning. In addition, in order to obtain better fasting blood sugar results, some patients will deliberately eat less staple food the night before the examination, which makes the fasting blood sugar value lower than usual. Therefore, in order to ensure the authenticity of fasting blood sugar the next morning, dinner must be kept at a normal state.
2. Time factor: Fasting blood glucose measurement must be completed before 8:00 am. However, it often happens that in order to see a doctor, many patients rush to the hospital from home without eating or drinking in the morning, and then register for treatment. They often have to wait until after 9:00 to 10:00 in the morning for their turn to see the doctor to test their blood sugar. Although the patient is in a fasting state at this time, due to the influence of the biological clock, glucagon hormone has gradually increased after 8:00. Even if he does not eat, his blood sugar will rise accordingly. Therefore, what is measured at this time is no longer the true fasting blood sugar, but only random blood sugar. In addition, some patients walk a relatively long distance to the hospital for treatment, so the blood sugar measured may be lower than usual; if the waiting time for treatment is too long, the mood is unhappy, emotional, etc., the blood sugar may be lower again. rise. For patients with type 1 diabetes, delaying or delaying the morning insulin injection will lead to a significant increase in blood sugar. The blood sugar measured in the above situations is not the true fasting blood sugar. Therefore, it is recommended that patients complete a fasting blood glucose test at home or at a nearby community health center, eat, take medicine or take insulin before going to the hospital for treatment.
3. Exercise factors Improper morning exercise is a common cause of affecting fasting blood sugar. Therefore, when we ask to check fasting blood sugar, it should be done without morning exercise. Because blood sugar generally decreases after exercise, if blood sugar rises instead, it may be due to mild hypoglycemia during exercise. Hypoglycemia can lead to reactive blood sugar increases. These are unrealistic fasting blood glucose results. Many people like to do morning exercise first and then have breakfast. This approach is unscientific and can easily cause hypoglycemia. It is best to eat something before morning exercise. When exercising in the morning, check your blood sugar before and after exercise to find an appropriate amount of exercise.
4. Drug factors Drugs are an important factor affecting fasting blood glucose results. If the dose of insulin in the evening is too large, it will lead to Sumuji's phenomenon and abnormally high fasting blood sugar in the morning. Furthermore, if some patients find that their fasting blood sugar is high, they intentionally eat less breakfast or take additional hypoglycemic drugs with meals. This will cause the fasting blood sugar to be higher than the blood sugar 2 hours after breakfast. Some patients take health products containing hypoglycemic drugs, which can also affect fasting or postprandial blood sugar.
5. Sleep factors American scientists divide a day’s sleep time into three categories: sleep <6 hours, sleep between 6 and 8 hours, sleep >8 hours, and observe the impact of sleep time on blood sugar. During the six-year study period, it was found that those who slept <6 hours a day had 4.56 times more blood sugar than those who slept between 6 and 8 hours. There was no difference between those who slept >8 hours and those who slept between 6 and 8 hours. It can be seen that patients with diabetes who sleep less than 6 hours a night can easily cause abnormal fasting blood sugar. To obtain true fasting blood sugar, you must ensure sufficient sleep time the night before.
6. Stress factors: recent bad mood, anxiety and depression, insomnia and dreaminess, may cause fasting blood sugar to be higher than usual, which cannot reflect the true effect of the drug or the condition. In addition, if acute infection or trauma occurs, stress factors often lead to elevated blood sugar. Some patients suffer from gastroenteritis, nausea and vomiting, cannot eat, and stop taking medicine. Some patients think that they do not need to inject insulin if they do not eat, thus leading to severe hyperglycemia... The fasting blood sugar measured in these cases cannot reflect the true basis. Fasting blood glucose must be treated symptomatically rather than adjusting antidiabetic drugs.
7. Monitoring methods and blood glucose meter factors This is a very common factor that affects whether fasting blood glucose is real or not, and it is also something we often mention. Diabetes patients use the blood glucose meter incorrectly, the blood glucose meter itself is unqualified or has not been calibrated for a long time, the test paper has expired or is damp, etc., which will affect blood glucose results.
