As the number of elderly people in society increases then the number of those with diabetes will increase. The prevalence of diabetes varies both geographically and between different ethnic groups. The large population study NHANES 2 in the USA showed rates of 9.3% and 8.4% for diagnosed and undiagnosed diabetes, respectively, in those aged 66-74 years. These figures have been roughly corroborated, using similar diagnostic criteria, in a more recent population-based study in Italy (10% and 5% respectively). Although known risk factors for non-insulin-dependent diabetes mellitus (NIDDM) such as family history, obesity and central distribution of fat are important in the elderly, aging itself seems to be a stronger risk factor.