Classification criteria and reporting standards
Global estimates 
Methodology
Results
Discussion

At a glance

Diabetes mellitus and lesser forms of glucose intolerance, particularly impaired glucose tolerance (IGT), can now be found in almost every population in the world and epidemiological evidence suggests that, without effective prevention and control programmes, diabetes will likely continue to increase globally   1 .

Type 1 diabetes usually accounts for only a minority of the total burden of diabetes in a population; it is the predominant form of the disease in younger age groups in most developed countries. Type 1 diabetes is increasing in incidence in both developing and developed countries, and there is an indication of a shift towards type 1 diabetes developing in children at earlier ages (see Diabetes in the young).

Type 2 diabetes constitutes about 85 to 95% of all diabetes in developed countries   1 , and accounts for an even higher percentage in developing countries. Type 2 diabetes is now a common and serious global health problem, which, for most countries, has evolved in association with rapid cultural and social changes, ageing populations, increasing urbanization, dietary changes, reduced physical activity and other unhealthy lifestyle and behavioural patterns   1 .

Figure 1 highlights the large range of type 2 diabetes prevalences even within the same or similar ethnic groups, when living under different conditions. Clearly, many of the differences between these rates reflect underlying behavioural, environmental and social risk factors, such as diet, level of obesity and physical activity.

Figure 1 | Differences in the prevalence of type 2 diabetes among selected ethnic groups, 2007

Within ethnic groups, high rates of type 2 diabetes are usually found in migrant or urbanized populations that may have experienced a greater degree of lifestyle change. The lowest rates are generally found in rural communities where people have lifestyles incorporating high levels of physical activity.

The incidence and prevalence of type 2 diabetes is also reported to be increasing in children. Studies from America and Japan have demonstrated an increasing incidence   2   3 , while other ethnic groups with high adult diabetes prevalence such as the Pima Indians   4  are also reporting increasing adolescent prevalences (see Diabetes in the young).