To determine the prevalence and associated risk factors of non-insulin-dependent diabetes mellitus (NIDDM) in inhabitants of traditional indigenous communities from Durango, Mexico, a transversal descriptive study was conducted. Tepehuano, Huichol and Mexicanero tribe members without racial admixture and a minimal Western influence on lifestyle were studied. One hundred and ninety-three subjects were included, this figure corresponding to approximately 20% of subjects aged from 30 to 64 years of the target population. Glycemia was determined in capillary blood after an overnight fast of 10-12 h, and 2 h after a 75 g oral glucose load using a Glucometer II device; NIDDM diagnosis was established according to the WHO criteria. Personal risk factors of NIDDM were determined. The average glucose level was 87.5 +/- 19.3 mg/dl. There were no NIDDM cases, hence the prevalence was 0.0%. The personal risk factors profile for NIDDM were as follows: 0.0% of cases with family history of NIDDM and with residency in urban areas > 40% of their lifetime, 7.2% of obese subjects and 15.5% of subjects with alcohol intake > or = 8 g/day. The absence of NIDDM suggests that this disease may be rare in traditional indigenous communities of Mexico and may be associated with less exposure to risk factors or genetic differences.