The fasting plasma glucose (FPG) test or fasting blood sugar test, which measure blood sugar or glucose levels and is useful in diabetes diagnosis. It is a simple, relatively reliable, and inexpensive test for diabetes diagnosis.
What is fasting blood sugar test?
Fasting triggers a glucagon hormone, when there is no longer enough glucose in blood for energy. The pancreas produces glucagon hormone, and it instructs the liver to convert stored glycogen to glucose and release it into the bloodstream for energy requirements.
Once liver releases glucose into the bloodstream, normal body immediately releases insulin to prevent hyperglycemia (high blood glucose). However, for diabetics, there is no longer enough insulin secretion or improper use of available insulin, thus fasting blood-glucose level stays high.
Fasting Plasma Glucose Test procedure
For FPG test, you require to have been fasting for at least 12 to 14 hours (must not to eat or drink anything except water for 12 to 14 hours). Because of this prolong fasting; the test is convenient to have in the morning.
Blood glucose levels: FPG test can be mention with different measurement units; they are:
- milligrams per deciliter (mg/dl), is the unit to measure that shows ‘x’ milligrams of glucose in the blood plasma per deciliter of blood, Blood glucose level in mg/dl is the unit used in United States.
- millimoles per liter (mmol/L), is the unit of measure that shows 'x' mmol concentration of glucose in the blood plasma per liter of blood. In most part of the world (except United States) uses this unit for blood-glucose test results.
|Diabetes Blood Glucose Level Signal|
Diabetes: Blood glucose level more than 126 mg/dl or 7 mmol/L is confirmed as diabetes.
Pre-diabetes: 100 to 126 mg/dl or 5.56 to 7 mmol/L is pre diabetes (impaired fasting glucose).
Non-diabetic: Glucose level of 70 - 99 mg/dl (3.89 - 5.5 mmol/L) is considered normal.
Hypoglycemia blood glucose levels
Blood glucose levels lower than 70 mg/dl is considered as hypoglycemia.
Blood glucose levels lower than 3.89 mmol/L is considered as hypoglycemia.
Even if the results are within the normal range, additional testing may be ordered to determine if a person has additional risk factors for diabetes, such as high body mass index (BMI), or if exhibits other symptoms of diabetes.
Also if the test result confirms diabetes at the border line level, then doctor may order another test on another day to reconfirm diabetes.