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Am I at risk
of prediabetes ?

Am I at risk
of prediabetes ?


As there are no obvious symptoms for prediabetes, there's often no reason to suspect you might be prediabetic.1 However, there are a number of factors that increase your risk of prediabetes. If you recognise any of these risk factors in yourself, you may want to talk to your doctor about your concerns and about testing your blood glucose levels.

Risk Factors2, 3, 4, 5, 6


Being overweight

If you are overweight or obese (i.e. with a body mass index (BMI) over 25 kg/m2 (or over 23 kg/m2 in Asians) there is more pressure on the body's ability to use insulin to properly control blood glucose levels.

Lack of exercise

Physical inactivity can impair glucose control.


You are at a greater risk of prediabetes if you are aged 45 years and over.

Family history

If your close relatives have diabetes, it is more likely that you will also be at risk of developing diabetes or prediabetes, as both genetic and environmental factors are important.

History of gestational diabetes

If you’ve had diabetes during pregnancy or have given birth to a child weighing more than 9 pounds (approximately 4 kg).

Race and ethnicity

There is a higher prevalence of type 2 diabetes in certain ethnic groups, including African, Native American, Latin American or Asian/Pacific Islanders.


If you have high blood pressure (i.e. above 140/90 mmHg) you are at an increased risk of developing diabetes.

Cholesterol levels

You are at increased risk if you have high-density lipoprotein (HDL) cholesterol (good cholesterol) below 35 mg/dL (0.90mmol/L) and/or a triglyceride level above 250 mg/dL (2.82 mmol/L).

Polycystic ovary syndrome (PCOS)

PCOS occurs when a woman's hormones are out of balance and has also been linked to increased risk of diabetes.

What tests can tell me if I am prediabetic?

If you think you are at risk of prediabetes, there are tests that can be performed to find out whether you are prediabetic. Your doctor will decide which tests are appropriate. The most common tests are:  


Fasting plasma glucose

This test checks how your blood glucose levels are maintained after fasting (not having anything to eat or drink except water) for at least 8 hours. This is generally done in the morning after an overnight fast, and your blood is tested to assess the level of glucose present.1

Oral glucose tolerance test (OGTT)

This test measures your body's ability to respond to glucose. After an 8-hour fast, you will be asked to drink a sweet liquid containing a measured amount of glucose (usually 75g). Your blood glucose levels before and 2 hours after this drink (the glucose load) are then measured to understand how your body reacts to the glucose following the fast.1, 7, 8

Haemoglobin A1c (HbA1c)

When glucose is in the bloodstream, it naturally attaches to red blood cells, which contain a protein called haemoglobin. These red blood cells are then said to be ‘glycated’. The HbA1c test measures this level of glycated haemoglobin. Red blood cells tend to survive for approximately 4 months before renewal; because of this, the HbA1c test can be used to accurately estimate your average blood glucose levels over the past 2–3 months. This provides a useful longer-term measurement of blood glucose control. There is no need to fast when this test is performed.1

What are the criteria for identifying prediabetes?

If you are prediabetic, your blood glucose is raised above normal levels, but is not high enough to be diagnosed with diabetes.1, 9 The exact amount it needs to be raised by to be identified as prediabetic varies slightly in the criteria published by the World Health Organization (WHO) and the American Diabetes Association (ADA).1, 10 The raised blood glucose seen in prediabetes increases the risk of type 2 diabetes.1 Identifying prediabetes now can be your chance to make positive changes and give yourself a second chance.

During the development of diabetes, fasting blood glucose, oral glucose tolerance and HbA1c levels increase.10, 11 Once levels rise into the prediabetic ranges, you are at a greater risk of developing diabetes. If you think you may be prediabetic, your doctor can perform tests to measure your blood glucose levels. If you know your results, you can enter them here…


Select a test:

Enter your blood sugar level:

mmol/dL| mg/dL


More than...

Less than or equal to ...


More than ...

Less than or equal to ...



More than 6.9 mmol/dL

Less than or equal to 6.9 mmol/dL


More than 5.5 mmol/dL

Less than or equal to 5.5 mmol/dL



More than 125 mg/dL

Less than or equal to 125 mg/dL


More than 99 mg/dL

Less than or equal to 99 mg/dL



More than 11.0 mmol/dL

Less than or equal to 11.0 mmol/dL


More than 7.7 mmol/dL

Less than or equal to 7.7 mmol/dL



More than 199 mg/dL

Less than or equal to 199 mg/dL


More than 139 mg/dL

Less than or equal to 139 mg/dL



More than 6.4%

Less than or equal to 6.4%


More than 5.6%

Less than or equal to 5.6%


*According to the American Diabetes Association (ADA) guideline definitions

Criteria differences for detecting prediabetes

Criteria for

World Health
Organization (WHO)

American Diabetes
Association (ADA)
Impaired fasting glucose (IFG) 6.1 - 6.9 mmol/L
(110 - 125 mg/dL)
5.6 - 6.9 mmol/L
(100 - 125 mg/dL)
Oral glucose tolerance test
(OGTT; blood glucose 2h after of 75g oral glucose)
7.8 - 11.1 mmol/L
(140 - 200 mg/dL)
7.8 - 11.0 mmol/L
(140 - 199mg/dL)
HbA1c Not considered a suitable test for prediabetes 5.7 - 6.4%


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

2. 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

3. WebMD. Risk Factors for Prediabetes. Available at: http://www.webmd.com/diabetes/risk-factors-for-prediabetes Accessed September 2017

4. NHS Choices. Type 2 diabetes - Causes. Available at: http://www.nhs.uk/Conditions/Diabetes-type2/Pages/Causes.aspx Accessed September 2017

5. WebMD. 12 Things That Make Type 2 Diabetes More Likely. Available at: http://www.webmd.com/diabetes/type-2-diabetes-guide/risk-diabetes Accessed September 2017

6. Science Daily. Inactivity linked to risk factors for Type 2 diabetes. Available at https://www.sciencedaily.com/releases/2011/08/110823165448.htm Accessed September 2017

7. WebMD. Oral Glucose Tolerance Test. Available at: http://www.webmd.com/diabetes/gestational-diabetes-guide/oral-glucose-tolerance-test#1 Accessed September 2017

8. Mayo Clinic. Glucose Tolerance Test. Available at: http://www.mayoclinic.org/tests-procedures/glucose-tolerance-test/basics/why-its-done/prc-20014814 Accessed September 2017

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

10. WHO. Definition and Diagnosis of Diabetes Mellitus and Intermediate Hyperglycemia. 2006

11. Mayo Clinic. Type 2 Diabetes. Available at: http://www.mayoclinic.org/diseases-conditions/type-2-diabetes/diagnosis-treatment/drc-20351199 Accessed September 2017