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FBS (Fasting Blood Sugar)

Also known as FBG (Fasting Blood Glucose), Glucose - Fasting (F), Fasting Blood Sugar

You need to provide

Blood, Urine, Stool, Nasal Swab, Throat Swab, FNAC, Nail

This test is for

Male, Female

Test Preparation

Overnight fasting (8-12 hrs) is required. Do not eat or drink anything except water before the test.

Understanding FBS (Fasting Blood Sugar)

What is FBS (Fasting Blood Sugar)?

An FBS (Fasting Blood Sugar) test measures the level of glucose (sugar) in the blood after a period of overnight fasting. This test is done when a person experiences symptoms of high or low blood sugar levels, or to assess a person’s risk for diabetes. It is often done as part of a routine health checkup.

Glucose is the primary energy source for the body. Carbohydrates in your food are broken down into glucose that is then absorbed into the bloodstream and transported to your cells for energy. Insulin, produced by the pancreas, regulates the level of blood glucose in the body. A lack of insulin or its reduced effectiveness can result in high blood glucose levels.

High blood glucose levels can be a sign of diabetes or prediabetes (a condition where a person has high blood glucose levels but not yet at a level that qualifies as diabetes). Early detection and treatment of diabetes are important to prevent complications such as heart disease, kidney damage, and nerve damage. An FBS test helps screen for prediabetes and diabetes and also checks the effectiveness of medications or lifestyle changes for the diagnosed people.

Fasting for at least 8-12 hours is recommended before undergoing an FBS test. Do not eat or drink anything other than water during the fasting period. It is also important to inform your doctor about any medicines you are taking, as some of them may affect your blood glucose levels and need to be adjusted or temporarily discontinued before the test.

Test result ranges are approximate and may differ slightly between labs depending on the methodology and laboratory guidelines. Talk to your doctor about your specific test results. The results will help them determine your medical condition, make recommendations for lifestyle modifications such as diet and exercise, determine whether or not medication will be required to manage your condition, and formulate your overall treatment plan.

What is FBS (Fasting Blood Sugar) used for?

A FBS (Fasting Blood Sugar) test is done:

As part of routine health checkups to measure the levels of glucose in the blood.
If you have symptoms of altered blood glucose levels, such as weight gain, weight loss, blurred vision, frequent urge to urinate, or confusion.
For assessing the risk for diabetes and prediabetes, and for monitoring diabetes treatment.
To screen pregnant women for gestational diabetes.

What does FBS (Fasting Blood Sugar) measure?

A fasting blood sugar test measures the level of glucose in the body under overnight fasting conditions. Glucose serves as the energy currency of the body and is broken down through metabolism to produce energy. This process is controlled by hormones and enzymes in organs such as the liver and pancreas. The hormone insulin, produced by the pancreas, is responsible for regulating blood glucose levels. When these levels are high, such as after a meal, insulin is secreted to transport glucose into cells for energy production. Elevated glucose levels in the body after fasting may indicate a risk of developing prediabetes or diabetes, which can be of two types- Type 1, caused by little or no insulin production, and Type 2, caused by insulin resistance or decreased insulin production.

Interpreting FBS (Fasting Blood Sugar) results

Interpretations

Normal fasting glucose range: 70 to 99 mg/dL (3.9 to 5.5mmol/L)

Prediabetes: 99 to 126 mg/dL (5.5mmol/L to 7.0mmol/L)

Diabetes: Higher than 126 mg/dL (7.0mmol/L) in multiple subsequent tests

Answers to Patient Concerns & Frequently Asked Questions (FAQs) about FBS (Fasting Blood Sugar)

Frequently Asked Questions about FBS (Fasting Blood Sugar)

Q. What is a fasting blood sugar test?

A fasting blood sugar or glucose fasting test measures the level of glucose (sugar) in the blood after a period of fasting, typically for at least 8-12 hours.

Q. Why is a glucose fasting test important?

A glucose fasting test is important because it helps assess a person's risk for serious health problems, like diabetes and other glucose metabolism disorders. It also helps monitor blood sugar levels over time in people with diabetes.

Q. How do I prepare for a glucose fasting test?

To prepare for this test, do not eat or drink anything except water for 8-12 hours before the test. It is also important to inform your doctor about any medications you are taking, as some of them can affect blood glucose levels and may need to be adjusted or temporarily discontinued before the test.

Q. What are the risks associated with a fasting blood sugar test?

The risks associated with a fasting blood sugar test are generally minimal. However, some people may experience mild pain or discomfort at the site from where the blood sample is taken.

Q. Can I take a glucose fasting test during pregnancy?

Yes, glucose fasting test is commonly used during pregnancy to screen for gestational diabetes, which is a type of diabetes that develops during pregnancy.

Q. What are the symptoms of hypoglycemia?

Symptoms of Hypoglycemia include: Excessive sweating, frequent hunger, shivering or trembling, confusion and blurring of vision

Q. What are the risk factors for diabetes?

Diabetes can be caused by various reasons. The most common risk factors for diabetes include being obese or overweight with low physical activity, having a blood relative diagnosed with Diabetes, or having been diagnosed with hypertension. Other reasons which can cause diabetes could be low High-Density Lipoproteins or high triglyceride levels, being diagnosed with Polycystic Ovarian Syndrome, or having been diagnosed with gestational diabetes and cardiovascular diseases.

Q. Can factors other than hormones and diet affect my blood sugar levels?

Yes, blood sugar levels can be increased by certain medications, during pregnancy, and even temporarily due to stress.

Q. What are the common complications of diabetes?

Diabetes causes an increase in blood sugar levels. Increased sugar levels, if not controlled, can cause severe damage to the muscles and nerves. This may give rise to a number of complications over a period of time. Some common complications of uncontrolled diabetes include heart diseases like coronary artery disease, heart attack, diabetic retinopathy (damage to the retina) which may cause blindness, diabetic neuropathy (damage to the nerves) at various parts of the body. It may also cause diabetic nephropathy (damage to the kidneys) resulting in chronic loss of kidney function and diabetic foot which can cause foot ulcers that may turn gangrenous. Apart from these, uncontrolled diabetes may also lead to other severe conditions like hearing impairment, a number of skin conditions, and may even lead to death.

Q. What other tests can be prescribed by your doctor in case the result of glucose fasting Glucose test is not normal?

Additional tests that may be prescribed to diagnose diabetes in case of abnormal glucose fasting test result are: Urine Glucose Test, Blood Glucose - Post prandial (PP), Random Blood Glucose Test, Glycosylated Hemoglobin Test or HbA1c Test and Oral Glucose Tolerance Test.

Q. How is the blood sample taken?

The healthcare provider takes a blood sample from the arm. The site from where the blood is to be withdrawn is cleaned with a swab of rubbing alcohol. This is then followed by inserting a small needle which has a tube attached to it for collecting blood. Once the sufficient blood for analysis is withdrawn, the needle is removed. The site is then covered with a gauze pad.

Q. What is hyperglycemia?

Hyperglycemia refers to a condition where the blood glucose level is above the normal range. This condition may indicate prediabetes or diabetes and may cause significant health problems.

Q. What are the symptoms of hyperglycemia?

Symptoms of Hyperglycemia include: Increased thirst, frequent urge to urinate, weakness, tiredness (fatigue), blurring of vision and slow wound healing.