The risk factors for type 1 diabetes are still being researched. However, having a family member with type 1 diabetes slightly increases the risk of developing the disease. Environmental factors and exposure to some viral infections have also been linked to the risk of developing type 1 diabetes.
Several risk factors have been associated with type 2 diabetes and include:
- Family history of diabetes
- Unhealthy diet
- Physical inactivity
- Increasing age
- High blood pressure
- Impaired glucose tolerance (IGT)*
- History of gestational diabetes
- Poor nutrition during pregnancy
Impaired glucose tolerance (IGT) is a category of higher than normal blood glucose, but below the threshold for diagnosing diabetes.
Changes in diet and physical activity related to rapid development and urbanisation have led to sharp increases in the numbers of people developing diabetes.
Pregnant women who are overweight, have been diagnosed with IGT, or have a family history of diabetes are all at increased risk of developing gestational diabetes (GDM). In addition, having been previously diagnosed with gestational diabetes or being of certain ethnic groups puts women at increased risk of developing GDM.
Know your risk of type 2 diabetes
Brief questionnaires are simple, practical and inexpensive ways to quickly identify people who may be at a higher risk of type 2 diabetes and who need to have their level of risk further investigated. The Finnish Type 2 Diabetes Risk Assessment Form, developed in 2001, is an example of an effective questionnaire that can be used as the basis for developing national questionnaires which take into account local factors. It has eight scored questions, with the total test score providing a measure of the probability of developing type 2 diabetes over the following 10 years. The reverse of the form contains brief advice on what the respondent can do to lower their risk of developing the disease, and whether they should seek advice or have a clinical examination. The test takes only a couple of minutes to complete and can be done online, in pharmacies or at various public campaign events. The questionnaire is available for download in several languages.
Reducing your risk of type 2 diabetes
There is a lot of evidence that lifestyle changes (achieving a healthy body weight and moderate physical activity) can help prevent the development of type 2 diabetes.
Obesity, particularly abdominal obesity, is linked to the development of type 2 diabetes. Weight loss improves insulin resistance and reduces hypertension. People who are overweight or obese should therefore be encouraged to achieve and maintain a healthy body weight.
Physical activity is one of the main pillars in the prevention of diabetes. Increased physical activity is important in maintaining weight loss and is linked to reduced blood pressure, reduced resting heart rate, increased insulin sensitivity, improved body composition and psychological well-being.
A balanced and nutritious diet is essential for health. A healthy diet reduces risk factors for cardiovascular diseases.
Other behaviors to consider include:
Smoking: a well-established risk factor for many chronic diseases, including diabetes and its complications. As well as other harmful effects, smoking increases abdominal fat accumulation and insulin resistance. All smokers should be encouraged to quit smoking. However, weight gain is common when quitting smoking and therefore dietary advice on avoiding weight gain should also be given (e.g. managing cravings and withdrawal symptoms by using short bouts of physical activity as a stress-relief activity, rather than eating snacks).
Stress and depression: There is evidence of a link between depression and both diabetes and cardiovascular disease.
Sleeping patterns: Both short (<6h) and long (>9h) sleep durations may be associated with a higher risk of developing type 2 diabetes. Sleep deprivation may impair the balance of hormones regulating food intake and energy balance. Long sleep durations may be a sign of sleep-disordered breathing or depression and should be treated appropriately. There is also a close association between obesity and obstructive sleep apnoea syndrome (OSA), the most common form of sleep disordered breathing.