Insulin production is usually greater than normal for many years, which maintains blood glucose and peripheral glucose disposal at normal levels, but as pancreatic B-cell insulin production slowly fails to meet the high-level demands of insulin resistance, insulin activity becomes insufficient to control blood sugar levels. Though many nutritional and genetic factors have been identified as contributing to the development of insulin resistance, the specific pathogenic mechanisms remain unclear and controversy surrounds the exact cause.
Type 2 diabetes, also called non-insulin dependent diabetes,is the most common form of diabetes and accounts for 85% of people with diabetes. Unlike Type 1 diabetes, Type 2 diabetes is preventable.
Although there is a strong genetic predisposition, lifestyle factors such as being overweight or obese combined with insufficient physical activity, a poor diet, and carrying too much weight around the waist area significantly increase the risk of developing Type 2 diabetes.
In Caucasian populations, the prevalence of Type 2 diabetes approaches 15-20% of the population and in certain indigenous communities the prevalence approaches 40-50% for the Pima Indians of Mexico, Nauru Islanders, Canadian Indians, Australian Aboriginals and Pacific Islanders. This variation in incidence is apparently related to genetic factors that have become concentrated in isolated indigenous hunter-gatherer communities.
Risk factors for Type 2 diabetes:
- Overweight or obese, especially around the waistline (>94cm for men and >80 cm for women)
- Sedentary lifestyle
- High triglycerides and low HDL-C and/or high total cholesterol,
- High blood pressure
- Family history of Type 2 diabetes and/or heart disease
- Age more than 55 years
- Age more than 45 year and overweight or high blood pressure
- Age more than 35 years and Aboriginal, Torres Strait Islander
- Certain ethnic backgrounds such as Aboriginal, Torres Strait Islander, Pacific Islands, Asia and the Indian subcontinent
- Woman who bore a child heavier than 4.5 kg
- Woman who developed gestational diabetes, or
- Woman with Polycystic Ovarian Syndrome.
Are you at risk?
A person who is overweight or obese risks developing Type 2 diabetes. In Australia, 75% of men and 50% of women are overweight or obese. In up to 60% of cases, the onset of Type 2 diabetes can be prevented or delayed. The Australian Type 2 diabetes risk assessment tool enables a person to assess his or her risk.
For many people the initial management may just require a change to a healthier diet, weight loss, and regular exercise. However, if blood sugar levels remain high medication and insulin may need to be taken to prevent long-term complications.