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Download the prediabetes infographic here and print it to raise awareness of prediabetes

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Download the prediabetes infographic here and print it to raise awareness of prediabetes



Prediabetes, also sometimes referred to as borderline diabetes or intermediate hyperglycemia, is a condition in which the blood glucose levels are higher than normal, but not high enough to be categorised as type 2 diabetes.1

The difference between prediabetes and diabetes lies in the level of blood glucose of the two conditions. The easiest test is measuring fasted blood glucose. This is a test that measures the level of glucose in the blood when a person has had nothing to eat or drink for at least 8 hours. According to ADA guidelines, a fasting blood glucose level between 100–125 mg/dL indicates that you are prediabetic. A fasting blood glucose level of more than 125 mg/dL indicates type 2 diabetes. Importantly, if prediabetes is not identified and persists, it may eventually develop into type 2 diabetes.2 Please note, guidelines may vary in different countries. 

Generally, there are no visible signs or symptoms associated with prediabetes. However, some people with prediabetes may have some of the symptoms of diabetes already.2 if you are prediabetic, it is very important to be aware of the symptoms of diabetes. If you notice any of these symptoms, ensure you visit your doctor. Symptoms include:3

  • Frequent urination
  • Feeling very thirsty
  • Feeling very hungry despite eating
  • Extreme tiredness
  • Blurred vision
  • Slowed healing
  • Numbness, tingling, or pain in the hands/feet  

There are several groups of people who are generally more at risk of developing prediabetes than others. If you fall into one of the risk categories outlined below, it may be a good idea to have regular health checks.4

  • Being overweight
  • Lack of physical activity
  • People aged 45 years and over
  • Family history of type 2 diabetes
  • History of gestational diabetes
  • People belonging to ethnic groups such as African, Native American, Latin American or Asian/Pacific Islanders
  • People who have high blood pressure (i.e. above 140/90 mmHg)
  • People who have HDL cholesterol (good cholesterol) below 35 mg/dL (0.90 mmol/L) and/or a triglyceride level above 250 mg/dL (2.82 mmol/L)
  • Polycystic ovary syndrome (PCOS)

Genes are likely to have a large role in the development of prediabetes5 as family history is a strong risk factor; however, your lifestyle is also proven to have a huge impact.4 For this reason, if you can make lifestyle changes now, you could prevent diabetes in the future!

Insulin resistance develops slowly over time, which leads to a loss in the ability to manage blood sugar levels, but what may trigger this on an individual basis is often not known. However, if you are overweight, are not physically active, and have a family history of diabetes, you are more likely to become prediabetic.4

The good news is that you can do something to prevent or delay diabetes. The high blood glucose in people with prediabetes can be reversed if identified early enough. However, if prediabetes is not identified and managed, it is very likely to progress to type 2 diabetes.6

The worldwide prevalence of prediabetes in 2010 was estimated to be 7.8% of the world’s population (approximately 343 million people). This prevalence appears to vary slightly in different parts of the world, ranging from 5.8% in South East Asia to 11.4% in North American and the Caribbean Countries.1 The Centers for Diseases Control and prevention (CDC) estimates prediabetes to affect 86 million Americans (49% of whom are under the age of 65 years). Importantly, it is estimated that 90% of people with prediabetes are completely unaware that they are prediabetic!7 The International Diabetes Federation has estimated that prediabetes will become more common in future years, and will affect up to 471 million people across the world by 2035!1

If you think you may be prediabetic, you must visit your doctor. Your doctor will likely advise lifestyle interventions such as an increasing your physical activity, eating a balanced diet and/or losing some weight. These lifestyle changes will also help you to avoid other health problems such as heart disease and stroke, diseases that are also linked to the development of type 2 diabetes. If lifestyles changes alone are unable to control your blood sugar level, your doctor can also discuss medications that might be able to help.6

Prediabetes is a warning sign that you are at risk of developing type 2 diabetes. However, by visiting your doctor and following his/her lifestyle advice or treatment recommendations, you can potentially reverse prediabetes and lower your blood glucose to within the normal range.8 Prediabetes can be your wake-up call; it’s time to make changes.

The risk of developing prediabetes can be reduced by making healthier food choices (such as limiting the intake of unhealthy foods and eating more fruits, vegetables, and other foods that are rich in nutrients and fibre), being more physically active, and losing excess body weight.2,8

It is difficult to tell whether you have prediabetes because there are no visible signs or symptoms. The only way to know is to check your blood glucose levels. However, you are at a higher than normal risk of having prediabetes if you are overweight, have a family history of diabetes, do not do regular physical activity, have high blood pressure or have high cholesterol. If you are in any of these categories and think you may have prediabetes, speak to your doctor.3,4  Take the test and find out if you are at risk of prediabetes.

To find out whether you have prediabetes, your doctor will check your medical history, perform a physical exam, and test your blood glucose levels. Blood tests used to identify prediabetes include a fasting plasma glucose test (FPG), a haemoglobin A1c test (HbA1c), and an oral glucose tolerance test (OGTT).9,10

For the fasting plasma glucose (FPG) test, a healthy fasting blood glucose level should be below 100 mg/dL. If your FPG concentration is between 100 and 125 mg/dL, you are considered to be prediabetic.2

For the oral glucose tolerance test (OGTT), your blood glucose is measured 2 hours after drinking a glucose-rich drink. Normal glucose levels are under 140 mg/dL. If your OGTT reading is between 140 and 199 mg/dL, you are considered to be prediabetic.2

To learn more about prediabetes and whether you may be at risk, please contact your doctor.

1. Bansal N. Prediabetes diagnosis and treatment: A review. World J Diabetes. 2015; 6(2): 296-303.

2. ADA. Diagnosing Diabetes and Learning About Prediabetes. 2014. Available at: http://www.diabetes.org/are-you-at-risk/prediabetes/. Accessed September 2017.

3. ADA. Diabetes Symptoms. Available at: http://www.diabetes.org/diabetes-basics/symptoms/ Accessed September 2017.

4. Diabetes Care. Standards in Medical Care in Diabetes—2015. Available at: http://care.diabetesjournals.org/content/suppl/2014/12/23/38.Supplement_1.DC1/January_Supplement_Combined_Final.6-99.pdf. Accessed September 2017

5. Mijajlovic MD, et al. Role of prediabetes in stroke. Neuropsychiatr Dis Treat. 2017; 13: 259-267.

6. Arch G. Mainous III P, Rebecca J. Tanner, MA, and Richard Baker, MD. Prediabetes Diagnosis and Treatment in Primary Care. Journal of the American Board of Family Medicine. 2015; 29: 283-285.

7. CDC. The Surprising Truth About Prediabetes. 2017. Available at: https://www.cdc.gov/features/diabetesprevention/index.html. Accessed September 2017.

8. Faerch K, et al. Pathophysiology and aetiology of impaired fasting glycaemia and impaired glucose tolerance: does it matter for prevention and treatment of type 2 diabetes? Diabetologia. 2009; 52(9): 1714-1723.

9. Tabak AG, et al. Prediabetes: a high-risk state for diabetes development. Lancet. 2012; 379(9833): 2279-2290.

10. Chatterjee R, et al. Screening adults for pre-diabetes and diabetes may be cost-saving. Diabetes Care. 2010; 33(7): 1484-1490.