Data from the National Health and Nutrition Examination Survey (NHANES) indicate that the trend toward increasing overweight and obesity among MexicanAmericans is continuing. This large population subgroup has a high prevalence of obesity and associated chronic conditions. Ethnic groups have different dietary patterns based on their geographical locations and various cultural influences. We examined the dietary patterns of Mexican-Americans and their association with total and central obesity. We hypothesized that Mexican-American adults following a traditional diet would have a lower prevalence of obesity than those following a more typically American diet. Data from the NHANES 2001-2002 included 835 adults, aged 18 and older. Dietary patterns were defined by cluster analysis of food group variables, expressed as percentage contribution to total energy intake. Obesity was assessed by body mass index (BMI, kg/m²) and central obesity by waist circumference. We defined four dietary patterns, each named after the food groups that were most predominant relative to the other clusters: poultry and alcohol, baked products, traditional foodstuffs (such as tacos, tortillas, etc.), and meat. Surprisingly, we did not identify a "healthy pattern" group in this population, as has been generally observed in other ethnic groups. Contrary to our hypothesis, the traditional diet pattern was associated with higher values of BMI and waist circumference. More details on possible changes within the traditional pattern associated with availability of foods and industrialization, including use of fast food vs. home-prepared Mexican foods, are needed to better understand the observed association with obesity.