Objective: Examine relationships of healthy and unhealthy dietary patterns with BMI, sex, age and acculturation among Mexican Americans. Design: Cross-sectional. Participants completed culturally tailored Healthy and Unhealthy Eating Indices. Multivariable mixed-effect Poisson regression models compared food pattern index scores and dietary intake of specific foods by BMI, sex, age and acculturation defined by language preference and generational status. Setting: Participants recruited from the Cameron County Hispanic Cohort study, Texas-Mexico border region, between 2008 and 2011. Subjects: Mexican-American males and females aged 18-97 years (n 1250). Results: Participants were primarily female (55(.)3 %), overweight or obese (85(.)7 %), preferred Spanish language (68(.)0%) and first-generation status (60(.)3 %). Among first-generation participants, bilingual participants were less likely to have a healthy eating pattern than preferred Spanish-speaking participants (rate ratio (RR)= 0(.)79, P = 0(.)0218). This association was also found in males (RR = 0(.)81, P= 0(.)0098). Preferred English-speaking females were less likely to consume healthy foods than preferred Spanish-speaking females (RR= 0(.)84, P = 0(.)0293). Among second-generation participants, preferred English-speaking participants were more likely to report a higher unhealthy eating pattern than preferred Spanish-speaking participants (RR= 1(.)23, P = 0(.)0114). Higher unhealthy eating patterns were also found in females who preferred English v. females who preferred Spanish (RR= 1(.)23, P= 0(.)0107) or were bilingual (RR= 1(.)26, P = 0(.)0159). Younger, male participants were more likely to have a higher unhealthy eating pattern. BMI and diabetes status were not significantly associated with healthy or unhealthy eating patterns. Conclusions: Acculturation, age, sex and education are associated with healthy and unhealthy dietary patterns. Nutrition interventions for Mexican Americans should tailor approaches by these characteristics.