Blood glucose levels that are higher than normal but not as high enough to be diagnosed with diabetes, is called prediabetes.
High blood glucose levels after eating a meal is due to impaired glucose tolerance [IGT]) and high blood glucose levels after not eating for 8 or more hours is called impaired fasting glucose [IFG]). Prediabetes puts you at higher risk of developing Type 2 diabetes. Prediabetes is associated with obesity (especially around the abdomen or around the internal organs), an abnormal amount of cholesterol and/or fat in the blood (known as dyslipidemia) and high blood pressure.
To prevent or delay the development of Type 2 diabetes, it is recommended that people with prediabetes try to reduce their body weight by 10% and increase physical activity to at least 30 minutes daily of moderate activity such as walking. Medication such as the oral blood glucose-lowering drug metformin may also be prescribed to help improve glucose tolerance.
Everyone is different and individuals can have different signs and symptoms. Sometimes there are no symptoms. Some of the signs are:
The onset of Type 1 diabetes is usually sudden, with symptoms that can be dramatic. The onset of Type 2 diabetes is more subtle, with mild symptoms or no symptoms.
ADA 2013: Standards of Medical Care in Diabetes http://care.diabetesjournals.org/content/36/Supplement_1
WHO Factsheet 312 http://www.who.int/mediacentre/factsheets/fs312/en/
Diabetes.co.uk, 2012: http://www.diabetes.co.uk/pre-diabetes.html
Diabetes.co.uk, 2012 http://www.diabetes.co.uk/pre-diabetes-faqs.html