Ethnic comparisons in diabetes and insulin levels.
The prevalence of non insulin dependent diabetes mellitus (NIDDM) is increasing exponentially. While the genetic causes of NIDDM remain unclear, the differences in prevalence of NIDDM over time, between and within different ethnic groups highlight the importance of environmental factors in the development of NIDDM in any given individual. Besides the classical risk factors for NIDDM such as obesity and indolence, the role of intra-uterine over-exposure or deficit of nutrients is increasingly felt to be of importance in the aetiology of NIDDM. Indeed, ethnic differences in hyperinsulinaemia, can be detected at birth in some populations. In utero exposure to increased fuel supply may be of particular importance in Polynesian and American Indian populations. If this is so, efforts to control NIDDM will take several generations to be successful.