Methods and rationale to assess the efficacy of a parenting intervention targeting diet improvement and substance use prevention among Latinx adolescents.

Latinx adolescents are at higher risk for chronic diseases relative to adolescents of other ethnic groups, in part because of their lack of adherence to diet recommendations and their higher rates of substance use. Given the proximal influence of family factors during the developmental stage of adolescence, parenting interventions may be an effective way to promote healthy nutrition and substance use prevention simultaneously. This article describes the design and theoretical rationale of a study assessing the effects of Families Preparing the New Generation Plus (FPNG Plus), a 10-week culturally-tailored nutrition and substance use prevention parenting program, on diet and substance use outcomes among Latinx middle school students (6th-8th grade). The 3-arm cluster randomized controlled trial compares FPNG Plus (substance use prevention and healthy nutrition), FPNG (substance use prevention only), and a comparison condition (focusing on academic success) in 1494 parent-child dyads from 18 schools, randomized at the school level. Adolescents and parents will complete surveys pre- and post-intervention, and 16-weeks after program participation, regarding diet behaviors, substance use, and parenting practices. A random subsample of 126 dyads (42 from each program), will participate in additional data collection to assess the home food environment, detailed dietary intake (via two 24-h recalls), and provide biomarkers of cardiometabolic risk (blood pressure, total cholesterol and HbA1c). If successful, this study will provide evidence contributing to helping Latinx parents assist their adolescent children develop and maintain long-lasting positive lifestyle behaviors in order to prevent concurrent substance use and diet-related chronic diseases.