- Diabetes Tests & What Diabetic Numbers Mean
- How to Test for Diabetes
- Home Diabetes Tests
- Glucose & Diabetic Test Strips
- Type 1 vs. Type 2 Diabetes Tests
- Fasting Plasma Glucose (FPG)
- Oral Glucose Tolerance Test (also called the OGTT)
- Random (also called Casual) Plasma Glucose Test
- What is Prediabetes?
- What are the ideal blood sugar levels?
Diabetes Tests & What Diabetic Numbers Mean
Diabetes has become the most common preventable disease in our society today. Because the symptoms of diabetes can be mild or even absent, tests performed by your doctor are the only way to ensure you are not developing diabetes or prediabetes.
Tests used both in the office and at home are important tools in the diagnosis and daily management of diabetes.
How to Test for Diabetes
Tests needed for the diagnosis of diabetes will be done at your doctors office. You will often need to fast overnight before having these blood tests performed.
The criteria for diagnosing diabetes includes:
1. Glucose >126 mg dl after 8 hours of fasting
2. Glucose >200 mg dl without fasting with symptoms of hyperglycemia
3. HbA1c (glycated hemoglobin) >6.5%
Sometimes these tests may be done more than once to make sure the diagnosis is correct.
Glucose Challenge Test
The glucose challenge test is a special exam for identifying diabetes in pregnancy. When a woman becomes pregnant she releases all sorts of hormones to support the baby growing inside of her. Unfortunately, some of these hormones make it harder for her body to process glucose, and thus put her at risk for developing a type of diabetes in pregnancy, called gestational diabetes.
Identifying gestational diabetes is so important because the disease can be very dangerous for both the mother and the baby she is carrying.
These complications can almost always be prevented by carefully managing the disease throughout pregnancy. Every pregnant women should be evaluated for gestational diabetes.
This test is most often done between 24 and 28 weeks of pregnancy with the glucose challenge test. It involves drinking a sugar filled drink at the doctors office. After one hour the blood sugar is checked. If the blood sugar is less than 140 mg dl it is considered normal. However blood glucose greater than 140 mg dl raises concern for gestational diabetes.
Hemoglobin A1c (HbA1c)
HbA1c is a great representation of the average blood glucose over the previous 3 months.
This is an important test because not only is it diagnostic of the disease but it helps to track progress of treatment. A lower HbA1c means that there has been consistent improvement in glucose control. In type 2 diabetics a normalized HbA1c combined with a normal fasting blood glucose can indicate resolution of the disease.
Home Diabetes Tests
Medical testing isn’t usually expected to be ‘do it yourself’.
But diabetics need to become experts at checking their own sugars and sometimes their own urine in order to effectively manage their disease.
The two main tests utilized at home in people’s everyday lives are blood glucose and ketones.
Glucose & Diabetic Test Strips
The mainstay test in diabetic care management is blood glucose. The overall goal is to keep blood glucose as close to normal as possible (70-140) and minimize any major fluctuations in sugar.
Type 1 diabetics should check their blood sugar at least 4 times daily including before meals and before going to sleep. This is because they are susceptible to rapid changes in their sugar based on their activity level, what they eat, and how much insulin they take. Their glucose measurements determine how much insulin they should give themselves and help to ensure their glucose levels aren’t getting too high or too low.
Type 2 diabetics should also check their glucose, but the frequency depends on how advanced their disease is. Some advanced type 2 diabetics who are now dependent on insulin may need to check their sugars as frequently as those with type 1. Others who develop type 2 diabetes and catch it early can be largely diet and exercise controlled. Their doctors may recommended that they have close follow up with only glucose checks at their doctors office.
How to Check Your Blood Glucose
Anyone on insulin or oral medications that can cause hypoglycemia should be aware of the symptoms of hypoglycemia and be able to regularly check their sugars.
You can check your real time glucose using a small portable machine called a glucometer. You prick yourself with a tiny needle included with the kit and place a drop of blood on the testing strip which is then entered into the glucometer to read your blood glucose.
Blood glucose can be dangerous if it is either too low or too high.
If your blood sugar is too low, you are said to have hypoglycemia. Hypoglycemia in diabetics is most often caused by medications, such as insulin.
While your body does have the potential to get energy from other sources (ie: glycogen), this process takes time. A fast drop in blood sugar that doesn’t allow your body the time to make more glucose can be very dangerous.
It’s therefore important to recognize the symptoms of hypoglycemia, so you can treat it early to prevent dangerous consequences.
If your blood sugar is too high, your are said to have hyperglycemia. People with diabetes by definition will have high blood glucose levels if they’re not being actively treated. The goal is to lower blood sugar into a normal range through diet, exercise and medications, if they are prescribed.
People on insulin check how high their current blood sugar levels are to determine how much medicine they should be taking.
Ketones (aka ketone bodies) are the result of fatty acids being used for fuel when there isn’t enough glucose available to the cells.
In diabetics, ketones can represent a dangerous complication called diabetic ketoacidosis (DKA) as ketone levels can rise when there isn’t enough insulin present. Other factors can stimulate the presence of ketones including excessive alcohol use, the ketogenic diet, and starvation.
Diabetic Ketoacidosis (DKA)
Ketoacidosis usually develops in people with type 1 diabetes, however it can also occur in people with advanced type 2 diabetes.
Ketoacidosis most commonly occurs when people don’t take their insulin when they should. Other frequent triggers include infections and other major stressors on the body such as heart attacks.
People are encouraged to test their own ketones if they have early symptoms of DKA or very high blood sugars. This is especially true for people with type 1 diabetes and advanced type 2 diabetes as they are at a higher risk of developing DKA.
Diabetics who test positive for ketones should always be further evaluated by a doctor to make sure they aren’t in diabetic ketoacidosis.
How to Check for Ketones in Urine
Checking your urine for ketones is the most common way of checking for ketones. It’s easy and inexpensive. Test strips can be bought at almost any pharmacy or drug store and simply involve, well – peeing on a stick. Color changes on the stick indicate if ketones are present, and about how many.
While glucose in the urine (glucosuria) is a common finding in diabetics, it is not always an accurate diagnostic test and it also doesn’t influence immediate treatment.
Ketones can also be checked by blood tests (similar to a blood glucose testing strip) as well as by breathalyzers.
Type 1 vs. Type 2 Diabetes Tests
Sometimes it’s difficult to determine which type of diabetes a person has. There are additional blood tests that can help with sorting out type 1 from type 2 diabetics.
Higher levels of insulin are often found in type 2 diabetes as their problem is classically that they can produce insulin, it just doesn’t work well. People with type 1 diabetes should have lower levels of insulin.
C-peptide is a protein that is released with insulin by the pancreas. It is also classically low to normal in people with type 1 diabetes and often higher in people with type 2 diabetes.
Because type 1 diabetes is an autoimmune disease, parts of the immune system called antibodies can be used to help differentiate it from type 2 diabetes. In specific, antibodies against the pancreas (GAD65 and IA1 and ZnT8) have been associated with type 1 diabetes.
Unfortunately these are only present in about 70% of people with type 1 diabetes. This means that just because these antibody tests are negative, the diagnosis of type 1 diabetes can’t necessarily be excluded (1).
— Question:What is the normal range for blood sugar levels, and what blood sugar level constitutes a true emergency?
Answer:Now, in a normal individual we measure blood sugar under different circumstances. What we call fasting blood sugar or blood glucose levels is usually done six to eight hours after the last meal. So it’s most commonly done before breakfast in the morning; and the normal range there is 70 to 100 milligrams per deciliter.
Now when you eat a meal, blood sugar generally rises and in a normal individual it usually does not get above a 135 to 140 milligrams per deciliter. So there is a fairly narrow range of blood sugar throughout the entire day.
Now in our diabetic patients we see both low blood sugar levels that we call hypoglycemia, or elevated blood sugars, hyperglycemia. Now, if the blood sugar drops below about 60 or 65 milligrams per deciliter, people will generally get symptoms, which are some shakiness, feeling of hunger, maybe a little racing of the heart and they will usually be trenchant or if they eat something, it goes away right away. But if blood sugar drops below 50 and can get down as low as 40 or 30 or even 20, then there is a progressive loss of mental function and eventually unconsciousness and seizures. And of course that is very dangerous and a medical emergency.
On the other side, if blood sugar gets up above 180 to 200, then it exceeds the capacity of the kidneys to reabsorb the glucose and we begin to spill glucose into the urine. And if it gets way up high, up in the 400s or even 500s, it can be associated with some alteration in mental function. And in this situation, if it persists for a long time, we can actually see mental changes as well. So either too low or very exceedingly high can cause changes in mental function.
Next: What Does Fasting Blood Sugar (FBS) Mean And What Does FBS Tell You?
Previous: How Often Must I Exercise And What Kind Of Exercise Should I Do To Lower My Risk Of Developing Type 2 Diabetes?
There are several ways to diagnose diabetes. Each way usually needs to be repeated on a second day to diagnose diabetes.
Testing should be carried out in a health care setting (such as your doctor’s office or a lab). If your doctor determines that your blood sugar level is very high, or if you have classic symptoms of high blood sugar in addition to one positive test, your doctor may not require a second test to diagnose diabetes.
The A1C test measures your average blood sugar for the past 2 to 3 months. The advantages of being diagnosed this way are that you don’t have to fast or drink anything.
- Diabetes is diagnosed at an A1C of greater than or equal to 6.5%
|Normal||less than 5.7%|
|Prediabetes||5.7% to 6.4%|
|Diabetes||6.5% or higher|
Fasting Plasma Glucose (FPG)
This test checks your fasting blood sugar levels. Fasting means after not having anything to eat or drink (except water) for at least 8 hours before the test. This test is usually done first thing in the morning, before breakfast.
- Diabetes is diagnosed at fasting blood sugar of greater than or equal to 126 mg/dl
|Fasting Plasma Glucose (FPG)|
|Normal||less than 100 mg/dl|
|Prediabetes||100 mg/dl to 125 mg/dl|
|Diabetes||126 mg/dl or higher|
Oral Glucose Tolerance Test (also called the OGTT)
The OGTT is a two-hour test that checks your blood sugar levels before and 2 hours after you drink a special sweet drink. It tells the doctor how your body processes sugar.
- Diabetes is diagnosed at 2 hour blood sugar of greater than or equal to 200 mg/dl
|Oral Glucose Tolerance Test (OGTT)|
|Normal||less than 140 mg/dl|
|Prediabetes||140 mg/dl to 199 mg/dl|
|Diabetes||200 mg/dl or higher|
Random (also called Casual) Plasma Glucose Test
This test is a blood check at any time of the day when you have severe diabetes symptoms.
- Diabetes is diagnosed at blood sugar of greater than or equal to 200 mg/dl
What is Prediabetes?
Before people develop type 2 diabetes, they almost always have “prediabetes” — blood sugar levels that are higher than normal but not yet high enough to be diagnosed as diabetes.
Doctors sometimes refer to prediabetes as impaired glucose tolerance (IGT) or impaired fasting glucose (IFG), depending on what test was used when it was detected. This condition puts you at a higher risk for developing type 2 diabetes and cardiovascular disease.
No Clear Symptoms
There are no clear symptoms of prediabetes, so, you may have it and not know it.
Some people with prediabetes may have some of the symptoms of diabetes or even problems from diabetes already. You usually find out that you have prediabetes when being tested for diabetes.
If you have prediabetes, you should be checked for type 2 diabetes every one to two years.
Results indicating prediabetes are:
- An A1C of 5.7% – 6.4%
- Fasting blood sugar of 100 – 125 mg/dl
- An OGTT 2 hour blood sugar of 140 mg/dl – 199 mg/dl
Preventing Type 2 Diabetes
You will not develop type 2 diabetes automatically if you have prediabetes. For some people with prediabetes, early treatment can actually return blood sugar levels to the normal range.
Research shows that you can lower your risk for type 2 diabetes by 58% by:
- Losing 7% of your body weight (or 15 pounds if you weigh 200 pounds)
- Exercising moderately (such as brisk walking) 30 minutes a day, five days a week
Don’t worry if you can’t get to your ideal body weight. Losing even 10 to 15 pounds can make a huge difference.
What are the ideal blood sugar levels?
Share on PinterestSelf-monitoring blood sugar is essential for managing diabetes.
Monitoring blood sugar levels is an important part of diabetes management. The best monitoring plans often rely on both self-monitoring at home and doctor-ordered tests, such as A1C tests.
Many types of blood sugar monitor are available for self-monitoring. Most blood sugar monitors in the United States involve using blood obtained from a finger prick and testing strips. These give blood sugar readings in mg/dl.
Modern home blood sugar meters produce plasma glucose counts instead of whole blood glucose counts.
This allows for more accurate readings of daily blood glucose levels. It is also easier to directly compare the results of self-monitoring and doctor-ordered tests, as doctors also use plasma glucose counts.
Tracking daily blood sugar level changes can help doctors understand how well treatment plans are working. This can help them determine when to adjust medications or targets. It can also help reflect the impact of diet and exercise.
The frequency of blood sugar tests varies among individual treatment plans, as well as the type and stage of diabetes.
Recommendations for testing are as follows:
Type 1, adult: Check at least twice daily, up to 10 times. People should perform their tests before breakfast, at fasting, before meals, sometimes 2 hours after meals, before and after physical activity, and at bedtime.
Type 1, child: Check at least four times daily. People should perform their tests before meals and at bedtime. Tests may also be required 1–2 hours after meals, before and after exercise, and overnight.
Type 2, people taking insulin or other management medications: The recommended frequency of testing varies depending on insulin dosage and the use of any additional medications.
Those taking intensive insulin should test when fasting, before meals and bedtime, and sometimes overnight. Those taking insulin and additional medications should at least perform tests at fasting and bedtime. People taking background insulin and one daily premixed insulin injection should perform tests when fasting, before premixed dosages and meals, and sometimes overnight.
Those not taking noninsulin oral medications or managing blood sugar levels through dietary adjustments require much less frequent blood sugar testing at home.
Type 2, when there is a low risk of low blood sugar: Often, daily tests are not necessary. Performing tests at meal times and bedtime should reflect the real-time impact of lifestyle changes.
If a person is not meeting blood sugar goals or A1C targets, the frequency of testing should increase until levels return to within the normal ranges.
Gestational: Those following a course of insulin should perform tests at fasting, before meals, and 1 hour after meals. Those not taking insulin should perform tests at fasting and 1 hour after meals.
People with gestational diabetes should test more regularly during periods of physical and emotional stress, such as acute illness or depression.
Continuous glucose monitors (CMGs) are devices that are particularly helpful for people who have difficulty using blood sugar meters. CMGs have a sensor that the individual inserts into their skin to measure the amount of sugar in tissue.
There is a wide range of CMGs available to purchase online.
If blood sugar levels become much higher than or too far below the established targets, an alarm will sound. Some CMGs also track the changes in blood sugar level over the course of hours and display to the user whether levels are rising or falling.
A person should verify CMGs regularly by taking blood sugar levels with a finger-prick meter. It is best to perform tests at times when blood sugar levels are steady, so avoid testing straight after meals and bouts of physical activity.