Prediabetes, also known as “impaired glucose tolerance” or “borderline diabetes,” occurs when blood glucose levels are higher than normal, but not yet high enough to be diagnosed as diabetes. Prediabetes puts someone at a higher risk of complications such as stroke and heart attack, and also increases the risk for developing type 2 diabetes. About 86 million (37%) Americans over the age of 20 years are estimated to have prediabetes. There are three different tests your doctor can use to determine whether you have prediabetes:
- Hemoglobin A1c test
- Fasting plasma glucose test
- Oral glucose tolerance test
For the three tests above, here are the reference ranges your doctor might use to diagnose prediabetes, or impaired glucose tolerance if your blood glucose is found to be out of the normal range. Numbers that are higher than the ranges below could indicate type 2 diabetes and more testing may be needed.
- Hemoglobin A1c test: 5.7% – 6.4%
- Fasting plasma glucose test: 100-125 mg/dl
- Oral glucose tolerance test: 140-199 mg/dl
The National Diabetes Prevention program showed that making lifestyle modifications such as lowering weight, increasing physical activity, and making healthier food choices may be able to prevent or delay a type 2 diabetes diagnosis. In some cases, these changes may help blood glucose levels lower into normal ranges to where prediabetes is reversed.
Type 1 diabetes (previously known as juvenile-onset diabetes or insulin-dependent diabetes) occurs when the body undergoes an autoimmune reaction, where the body attacks itself, and destroys the cells in the pancreas that make insulin. Without insulin, the body cannot use blood glucose for energy and glucose levels remain elevated in the bloodstream. Those living with type 1 diabetes require insulin medication delivered by an injection or an insulin pump to survive. Type 1 diabetes most often occurs in people under the age of 30. In 2008-2009, it is estimated that roughly 18,500 people under the age of 20 years were diagnosed with type 1 diabetes annually. Currently there is no known way to prevent this type of diabetes but many trials are being done to advance type 1 diabetes management options. Type 1 diabetes cannot be reversed, but it can be managed extremely well. People with type 1 diabetes can live long healthy lives if blood glucose stays within a healthy range.
Type 2 diabetes (formerly called adult onset or non insulin dependent diabetes) occurs when the body either makes too little insulin or can’t efficiently use the insulin it makes, resulting in high blood glucose. Type 2 diabetes occurs most frequently in those over the age of 40, but more cases are starting to be seen in children. Type 2 diabetes risk factors include factors such as family history, older age, race/ethnicity, history of gestational diabetes, impaired glucose metabolism (such as prediabetes), obesity, lack of physical activity, and poor nutritional habits over time. Insulin resistance is a common occurrence within type 2 diabetes, where the body’s muscle, fat, and liver tissues do not use insulin correctly. Over time, the pancreas may lose its ability to produce needed amounts of insulin for the body. In order to manage type 2 diabetes, people may modify their eating patterns, increase physical activity, lose weight if needed, monitor blood sugar, and take medications such as pills and/or insulin if prescribed. Type 2 diabetes cannot be reversed, but it can be managed extremely well. People with type 2 diabetes can live long healthy lives if blood glucose stays within a healthy range.
Gestational diabetes, a form of glucose intolerance in pregnant women, is typically tested for and diagnosed in the second or third trimester of pregnancy. Gestational diabetes causes high blood glucose in these women and increases the mother and fetus’ risk for complications during pregnancy. Mothers with this form of diabetes may need to modify their eating patterns, increase physical activity, or take medications such as insulin. In most cases, gestational diabetes goes away after the birth of the baby, but 5-10% of women are diagnosed with diabetes (typically type 2 diabetes) if blood glucose does not go back to normal ranges after birth. Women who have gestational diabetes are at an increased risk for developing type 2 diabetes later in life. Also, research is being done to see if the baby may be at a higher risk of developing obesity and diabetes later in life.