Self-control strategies to reduce meat consumption: An ecological momentary intervention.

An increasing number of individuals aim to reduce their meat consumption, but implementing this is challenging. Self-control strategies could support this change; however, their effectiveness remains understudied. This study examines whether providing self-control strategies supports motivated individuals in reducing meat intake. Based on the process model of self-control, we tested whether situational strategies outperform intrapsychic strategies. Additionally, we examined whether combining both strategy types is more effective than either strategy alone. We conducted an ecological momentary intervention including a baseline (Week 1), an intervention (Weeks 2-4), and a follow-up (Week 9). Participants-156 German students who regularly consumed meat and aimed to reduce their consumption-were randomized to one of four groups: during the intervention, they received either no, intrapsychic, situational, or both strategies. Meat consumption (in grams) was measured through end-of-the-day reports. Two-part multilevel models showed that receiving strategies (vs. none) and receiving both strategy families (vs. one) increased the odds of meat-free meals during the intervention, but did not reduce overall meat consumption. All groups meaningfully reduced meat consumption during study participation, even up to the 1-month follow-up. Findings challenge the key prediction of the process model and inform the design of future diary interventions.