Causal explanations for weight influence children’s social preferences: Biological-essentialist explanations reduce, and behavioral explanations promote, preferences for thin friends

The current study experimentally investigated the impact of causal-explanatory information on weight bias over development. Participants (n = 395, children ages 4–11 years and adults) received either a biological or behavioral explanation for body size, or neither, in three between-subjects conditions. Participants then made preference judgments for characters with smaller versus larger body sizes. Results showed that both behavioral and biological explanations impacted children’s preferences. Relative to children’s baseline preferences, behavioral explanations enhanced preferences for smaller characters, and biological explanations reduced these preferences—unlike the typical facilitative impact of biological-essentialist explanations on other biases. The explanations did not affect adults’ preferences. In contrast to previous findings, we demonstrate that causal knowledge can impact weight bias early in development.