This test is invasive and conducted to measure the amount of glucose in the patient’s blood. For this test 100 milligrams per deciliter (mg/dL) is considered to be normal. Results ranging in between 100-125 mg/dL are signs of a type of pre-diabetes i.e. impaired fasting glucose. Among the different laboratories tests the normal value ranges may fluctuate faintly. This test is very simple, takes no more than 5 minutes and has no risks, except in some rare cases where hematoma ( accumulation of blood under the skin) and infection can take place. 

This invasive test can be conducted at any time irrespective of the fact that when was the food last consumed by the patient. A blood sample is taken and the test is run. If the test reflects a blood glucose level of 200 mg/dL or more proposes diabetes particularly coupled with one or more signs of diabetes such as too much thirst or recurrent urination. The range of sugar level between 140 mg/dL and 199 mg/dL proposes prediabetes, thereby putting a patient at a greater risk of developing diabetes.

The measurement of blood sugar is done by glucometer, which is a portable device. The normal glucose meter kit comes with special test strips, small needles called lancets and the glucometer. The patient needs to prick the finger with the needle and place a drop of blood on the strip, which uses a chemical substance to ascertain the amount of glucose in the blood. The values depend on the physical actions, food and insulin administration. The normal result is 70-130 mg/dL before meals and less than 180 mg/dL after the meals. This is also an invasive test. 

This test is a laboratory method of checking, how the body metabolizes the glucose. This test has a long procedure and can cause mental irritation and stress to the patient. For this test the patient is required not to consume anything after the midnight before the test. Before the test, the blood sample of the patient is taken and then asked to drink liquid that contains certain amount of glucose. Then the patient’s blood is taken every 30-60 minutes after the patient has taken the solution. The test continues up to 3 hours. The normal results for 100 gram OGTT are:

a. Fasting = >95 mg/dL

b. 1 Hour = >180 mg/dL

c. 2 Hour = >155 mg/dL

d. 3 Hour = >140 mg/dL

And normal blood values for 50 gram OGTT is:

1 Hour = >140 mg/dL

Though this test is very reliable but factors such as acute stress and vigorous exercise may affect the test results. 

In this invasive test, the patient’s body is injected with glucose solution, in the veins for approximately 2-3 minutes. The blood insulin levels are measured before injecting the glucose solution and then again after 1 & 3 minutes after the process of injection. The timing of recording the insulin level may vary. Though this test is very reliable but factors such as acute stress and vigorous exercise may affect the test results. But this test is generally used for type 2 diabetes. 

This test is conducted to have a record of the average amount of glucose in the blood for the past 3 months and to see how well the patient is controlling his/her diabetes. It’s an invasive test and doesn’t require any special preparations. The normal results are:

a. Normal = >5.7%

b. Pre-diabetes = 5.7% to 6.4%

c. Diabetes = 6.5% or greater

If one has diabetes, it’s prescribed to keep the level below 7%. This is also an invasive test.

Ketone testing is done generally in the cases of pregnancy or if the blood sugar level is higher than 240 mg/dL or in cases of nausea, pneumonia, heart attack, vomiting etc. This test is conducted to calculate the amount of ketones in the patient’s blood or urine. So, for this test blood or urine sample of the patient is required. Ketones are formed when the diet of a person doesn’t have much carbohydrates or if the body is unable to utilize the blood glucose properly. For the urine test, the results of the test is determined if the test strip or the urine sample changes color when the tablet is dropped in the sample thereby indicating the presence of ketones. The result of this test is read as negative to 1+ to 4+ or small to large. Moreover, this way of testing for diabetes is the only non-invasive way of testing for it.