Documentary films can increase nationwide interest in plant-based food

Plant-based diets can help mitigate climate change. We investigated longitudinal effects of popular media that encourage plant-based diets from diverse perspectives, including health, environment, and animal welfare. We systematically searched for the most popular such media, which were all films. In initial correlational analyses, Google search interest for the films explained the majority (73%) of variance in search interest for plant-based food, but was not associated with consumption of meat or of plant-based alternatives. In primary analyses using pre-registered causal inference models that controlled for confounding, we estimated that each 1-SD increase in search interest for the health-focused films What the Health (2017), The Game Changers (2018), and You Are What You Eat (2024) increased search interest in plant-based food by 43%, 11%, and 11% respectively in the following week. These results can inform communication approaches for ongoing efforts of governments and other organizations encouraging sustainable diets.