Effectiveness of a Theory-Informed Documentary to Reduce Consumption of Meat and Animal Products: Three Randomized Controlled Experiments.

Several societal issues could be mitigated by reducing global consumption of meat and animal products (MAP). In three randomized, controlled experiments (n=217 to 574), we evaluated the effects of a documentary that presents health, environmental, and animal welfare motivations for reducing MAP consumption. Study 1 assessed the documentary's effectiveness at reducing reported MAP consumption after 12 days. This study used methodological innovations to minimize social desirability bias, a widespread limitation of past research. Study 2 investigated discrepancies between the results of Study 1 and those of previous studies by further examining the role of social desirability bias. Study 3 assessed the documentary's effectiveness in a new population anticipated to be more responsive and upon enhancing the intervention content. We found that the documentary did not decrease reported MAP consumption when potential social desirability bias was minimized (Studies 1 and 3). The documentary also did not affect consumption among participants whose demographics suggested they might be more receptive (Study 3). However, the documentary did substantially increase to reduce consumption, consistent with past studies (Studies 2 and 3). Overall, we conclude that some past studies of similar interventions may have overestimated effects due to methodological biases. Novel intervention strategies to reduce MAP consumption may be needed.