Types

• Type 1 diabetes is an autoimmune condition where the body attacks the pancreatic beta cells that produce insulin. Symptoms usually appear before the age of 30. Latent autoimmune diabetes in adults, sometimes referred to as LADA or type 1.5, is a slower developing form of Type 1. Maturity-onset diabetes of the young (MODY) is a genetic form caused by beta cells defects.
  
  In Type 2 diabetes, the body is insulin resistant--unable to use insulin properly. Over time, the pancreas cannot make enough. Pre-diabetes is the phase before Type 2 is fully developed.
  
  

Glucose Test

• The oral glucose tolerance test, or OGTT, requires a fasting period of eight hours before the test. After a blood-glucose level check, the patient drinks 75 grams of glucose. Testing is most often done at the two-hour mark, but sometimes more often and for a longer period if other problems such as reactive hypoglycemia are a possibility. Glucose levels between 140 and 200 milligrams per deciliter of blood (mg/dL) in the two-hour test are pre-diabetic. A diabetes diagnosis is more than 200 mg/dL.
  
  

Fasting Test

• A fasting plasma glucose (FPG) test detects pre-diabetes and diabetes. Normally, it is performed in the morning after several hours fasting. Results between 100 and 126 mg/dL point to pre-diabetes; 126 mg/dL is considered diabetic. The FPG costs less than the OGTT and is often used, but it is not considered as accurate as the OGTT.
  
  

Casual Test

• Random plasma glucose tests are not as reliable as other tests, but they are easy to perform and can be done in a doctor's office rather than at the lab. Diabetes is a possibility with a blood sugar level over 200 when symptoms are present. Symptoms include weight loss, increased thirst and urination, difficulty healing and vision problems. A follow-up OGTT or FPG test confirms diagnosis.
  
  

Hemoglobin

• The A1C hemoglobin test shows the average blood glucose levels for the past two or three months. The American Diabetes Association sees a result of less than 7 percent as an indicator of good blood-glucose control. The International Diabetes Federation and the American College of Endocrinology both recommend keeping the number at less than 6.5 percent.