Several studies have clearly shown the impact of modernization on the prevalence of diabetes mellitus in susceptible communities. Saudi Arabia has faced a rapid development program over the last two decades. In a recent study, we found a high prevalence of diabetes mellitus in urban Saudi Arabia. A total of 5222 rural subjects of both sexes were involved in a study of the prevalence of diabetes mellitus in the western region of Saudi Arabia. Random capillary blood glucose, body weight and height, and income were recorded. The results showed an overall prevalence of 4.3%. There was a rise of prevalence with age and higher-income groups. Prevalence also differed with sex. The overall prevalence in women (5.9%) was twice that for men (2.9%; P less than .001). Obesity occurred in 41.2% of our diabetic subjects compared to 29.3% in nondiabetic subjects (P less than .001). Multiple logistic regression analysis with body mass index (BMI) as the dependent variable showed that sex and income status were significant factors (P less than .0001 and P less than .04, respectively). When blood glucose was fixed as the dependent variable, the analysis showed that age, income, and BMI were significant factors (P less than .004, P less than .0001, and P less than .045, respectively).