Not eating may give you a headache. And if you fast for more than a day or so, your body may not get enough of the nutrients it needs without supplements. But the biggest danger of fasting if you have diabetes is that your blood sugar levels could go dangerously low (this is called hypoglycemia).
IF YOU FAST LONGER THAN 16 HOURS - YOUR RESULTS MAY NOT BE ACCURATE, OR WE MAY NOT BE ABLE TO PERFORM SOME OF THE TESTS.
High levels of fasting blood sugar suggest the body was not able to lower blood sugar levels. This points to insulin resistance, inadequate insulin production, or in some cases, both. Very low blood sugar levels may indicate that diabetes medications are lowering the blood sugar too much.
The dawn phenomenon
In the early hours of the morning, hormones, including cortisol and growth hormone, signal the liver to boost the production of glucose, which provides energy that helps you wake up. This triggers beta cells in the pancreas to release insulin in order to keep blood glucose levels in check.
A blood sample will be taken after you haven't eaten anything the night before (fast). A fasting blood sugar level less than 100 mg/dL (5.6 mmol/L) is normal. A fasting blood sugar level from 100 to 125 mg/dL (5.6 to 6.9 mmol/L) is considered prediabetes.
Q: What is the normal range that your blood sugar should be if you test it at home? A: For a basically healthy person, a good fasting is under 100, and 80-90 is even better for most people.
The recommended blood glucose range after fasting in a person without diabetes is 70 to 130mg/dL.
For some people, blood sugar can rise in the morning -- even before breakfast -- due to changes in hormones or a drop in insulin. Regular testing is important.
The dawn phenomenon is an early-morning rise in blood sugar, also called blood glucose, in people with diabetes. The dawn phenomenon leads to high levels of blood sugar, a condition called hyperglycemia. It usually happens between 4 a.m. and 8 a.m.
However, various factors such as application errors, extreme environmental conditions, extreme hematocrit values, or medication interferences may potentially falsify blood glucose readings. Incorrect blood glucose readings may lead to treatment errors, for example, incorrect insulin dosing.
It is important to fast correctly, to obtain reliable blood test results. Fasting means nothing to eat or drink (except water) for 10–16 hours before your blood test. During your fasting period: • You may drink plain water, but it must not contain additives -no tea, coffee or cordials.
You usually need to fast for 8–12 hours before a test. Most tests that require fasting are scheduled for early in the morning. That way, most of your fasting time will be overnight.
Patients should not fast for longer than 12 hours. While fasting is critical to these blood tests' reliability and validity, over fasting can result in dehydration or other side effects. When fasting, remind patients that sleep also counts as fasting.
So people reduce their carb intake, go on a low carbohydrate diet, and focus on eating healthy fats and (in many cases) too much protein. But what this solution crucially fails to address is insulin resistance, which is the true cause of those high blood glucose numbers.
Normal blood sugar levels when you wake up
According to the American Diabetes Association, your blood sugar when you wake should be below 100 mg/dL (5.6 mmol/L) if you don't have diabetes.
Your body uses glucose (sugar) for energy and it is important to have enough extra energy to be able to wake up in the morning. So for a period of time in the early morning hours, usually between 3 a.m. and 8 a.m., your body starts churning out stored glucose to prepare for the upcoming day.
Starvation diet and very-low-calorie diets may induce insulin resistance and overt diabetes mellitus.
Fasting can cause a rise in blood sugar if your intermittent fasting routine causes you stress. If your blood sugar rises, your pancreas won't be able to keep up with producing enough insulin, which can lead to a whole host of health problems.
Less than 140 mg/dL (7.8 mmol/L ) is normal. 140 to 199 mg/dL (7.8 mmol/L and 11.0 mmol/L ) is diagnosed as prediabetes. 200 mg/dL (11.1 mmol/L ) or higher after two hours suggests diabetes.
Fasting blood sugar test
In general: Less than 100 mg/dL (5.6 mmol/L ) is normal. 100 to 125 mg/dL (5.6 to 6.9 mmol/L ) is diagnosed as prediabetes. 126 mg/dL (7.0 mmol/L ) or higher on two separate tests is diagnosed as diabetes.
This measures your blood sugar after an overnight fast (not eating). A fasting blood sugar level of 99 mg/dL or lower is normal, 100 to 125 mg/dL indicates you have prediabetes, and 126 mg/dL or higher indicates you have diabetes.
A normal blood sugar level is less than 100 milligrams per deciliter of blood (mg/dL) after an eight-hour fast. You have diabetes if your blood sugar is 126 mg/dL or higher.
Check your blood glucose immediately on awakening—before any morning activities, such as showering, shaving or putting on makeup. The reason for this schedule is that if your blood glucose is low, you can drink some juice or milk.
While not all lab tests require it, some tests require fasting for the most accurate results. Most of the time, this means you'll be asked to stop having any food or liquid between eight to 24 hours before your lab test or bloodwork, depending on the test.
Common fasting blood tests
a fasting blood glucose test (used to test for diabetes) – you may be asked to fast for 8 to 10 hours before the test. an iron blood test (used to diagnose conditions such as iron deficiency anaemia) – you may be asked to fast for 12 hours before the test.