BackgroundAmong Latinos, greater acculturation to the United States (US) is associated with risk of obesity and obesity-related comorbidities. Less is known about the associations between acculturation and obesity-related modifiable risk factors, such as diet quality and physical activity (PA) among Latina breast cancer survivors. ObjectiveThe aim of this study was to explore associations between acculturation and weight status, diet quality, and PA among Latina breast cancer survivors. DesignThis is a cross-sectional secondary analysis of baseline data on demographic and clinical characteristics, acculturation, anthropometric measures, diet quality, and PA collected from Latina breast cancer survivors enrolled in the ¡Mi Vida Saludable! (My Healthy Life) behavioral diet and PA intervention trial. Participants/settingParticipants were Latina women (n = 167) residing in New York City, with a medical history of stage 0 to III breast cancer, no evidence of recurrent or metastatic disease, and at least 90 days post cancer treatment who participated in the ¡Mi Vida Saludable! randomized controlled trial between July 2016 and October 2018. Main outcome measuresAcculturation status was measured by the Short Acculturation Scale for Hispanics score, language preference, place of birth, and duration of US residence. Weight, height, and waist and hip circumferences were measured at an in-person clinic visit. Diet information was collected via 3 telephone-based 24-hour dietary recalls and PA information was collected via staff administered 7-day recalls. Statistical analyses performedLinear regression models examined associations between acculturation and weight status, diet quality, and PA. ResultsBased on the Short Acculturation Scale for Hispanics acculturation score, more acculturated compared with less acculturated Latinas were younger in age, more educated, and had higher annual household incomes (all, P < .05). Compared with Spanish-speaking Latinas, English-speaking Latinas had larger waist circumference (103 vs 96.1 cm; P = .01) and poorer-quality diets (Healthy Eating Index 2015 scores, 57.3 vs 71.5; P < .001). Greater levels of acculturation were also associated with higher levels of leisure walking at a moderate-to-vigorous intensity (265.8 vs 179.0 min/wk; P =.04). ConclusionsGreater levels of acculturation were associated with higher central obesity and poorer-quality diets. Future lifestyle modification trials tailored to the unique role of acculturation on adopting behavior change recommendations is a promising next step in this line of research.