Diabetes is a chronic condition marked by high levels of glucose in the blood. The main types of diabetes are type 1 diabetes, type 2 diabetes and gestational diabetes. The prevalence of diabetes has been escalating over the last 3 decades, with rates tripling over this period—diabetes affected around 1.2 million people in 2014–15. Rates of diabetes are generally higher among males, the elderly, Indigenous Australians and people living in remote and socioeconomically disadvantaged areas. Type 2 diabetes is the most common form, and is largely preventable by maintaining a healthy lifestyle.