ObjectiveHyperinsulinaemia may be associated with hypertension, hyperlipidaemia and glucose intolerance. In the present study we compared the consequence of immigration from Ethiopia to Israel in order to elucidate environmental effects on these variables.DesignA cross-sectional analysis of 337 young, male Ethiopian immigrants who were placed in boarding schools were divided into two groups: group I was in Israel for <3 months (n = 180) and group II was in Israel for >2 years (n = 157). Both groups were attending the same schools and were fed from the same kitchens.MethodsSitting blood pressure, body mass index, triceps skinfold width, fasting lipids insulin and glucose levels were measured and a standard (75-g) oral glucose-tolerance test was performed.ResultsBoth groups had similar body mass index. Group I was younger than group II. Both systolic and diastolic blood pressure were significantly higher in group II than in group I. Hypertension was more prevalent in group II. Impaired glucose tolerance (from the oral glucose-tolerance test) prevalence did not differ between the groups, neither did the glycosylated haemoglobin nor fructosamine level. The insulinogenic index (ratio of the areas under the curve of the insulin to that of the glucose level during the oral glucose-tolerance test) was significantly higher in group II. Total and high-density lipoprotein-cholesterol levels were significantly higher in group II. In stepped multiple regression analysis, belonging to group II and having higher insulinogenic index predicted hypertension.ConclusionsThis cross-sectional comparison of young, very lean Ethiopian immigrants found those with longer residence in Israel and higher insulinogenic index to have a threefold increase in the prevalence of hypertension in addition to acquiring higher cholesterol levels, indicating that in this ethnically distinct population environmental factors significantly affected the cardiovascular risk.