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 (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 affect overall meat consumption reduction. All groups meaningfully reduced meat consumption, even up to the one-month follow-up, highlighting the effectiveness of self-monitoring. Findings challenge the key prediction of the Process Model and inform the design of future diary interventions.