Testing a Dissonance-Based Intervention to Reduce Ultra-Processed Food Consumption Via Activism Against the Food Industry

The DISRUPT clinical trial will test 2-month interventions for reducing ultra processed food (UPF) intake among 60 adults with overweight or obesity (ages 18-70) who frequently consume UPFs. Participants will be randomly assigned to receive a standard dietary change (SDC) intervention (ON/OFF), in which they will receive the typical toolbox of evidence-based methods for changing diet (e.g., meal planning, problem solving, reflecting on the benefits of change) to help them reduce their ultra-processed food intake. Participants will be also randomly assigned to receive a cognitive dissonance intervention (ON/OFF). In this intervention, participants will learn about the harms of the food industry and be engaged in activism against this industry to elicit cognitive dissonance for consuming UPFs. Participants will be randomly assigned to each condition separately (through a 2x2 factorial design, resulting in four possible experimental conditions: 1) Control (both OFF), 2) Standard Dietary Change Condition (SDC ON, Dissonance OFF), 3) Dissonance Condition (SDC OFF, Dissonance ON), and 4) SDC + Dissonance Condition (SDC ON, Dissonance ON).

All participants will receive an introductory educational workshop on UPFs, how to identify them, and their harmful health effects. Participants assigned to receive at least one of the interventions (i.e., SDC, dissonance, or both) will attend weekly group sessions for weeks 2-8.

Aim 1 is to test the isolated and interactive effects of standard behavior change strategies and dissonance-based strategies on treatment outcomes. Participants randomly assigned to the SDC condition and the Dissonance condition, respectively, are expected to have larger reductions in UPF intake, greater improvements in indicators of dietary quality (e.g., added sugar, sodium intake), and more weight loss, compared to those in the control condition. The effect of the SDC + Dissonance condition (vs. the control condition) on treatment outcomes is expected to be synergistic, greater than the additive effect either condition alone.

Aim 2 is to test the hypothesis that having the dissonance intervention ON will attenuate the disparity in treatment outcomes for individuals with socio-structural barriers to healthy eating (i.e., low perceived socioeconomic status, low income, limited access to healthy food, and unhealthy neighborhood food environment).