The study determined the prevalence of type 2 diabetes, abnormal glucose tolerance and other cardiovascular risk factors in a sample of 250 adults aged > or = 35 years in a semirural area near Sana'a, the capital of Yemen,. The overall crude prevalence of diabetes was 10.4% (95% CI: 6.6%-14.2%) and the age-standardized rate was 6.3% (95% CI: 5.4%-7.2%). The age-standardized rate of having either impaired fasting glucose or impaired glucose tolerance was 9.0% (95% CI: 6.0%-12.0%) and the age-standardized prevalence of hypertension was 14.2% (95% CI: 13.0%-16.0%). Age and waist circumference were independently related to total glucose intolerance. The observed high frequency of central obesity suggests a dietary origin for these adverse health conditions.