Many people in Western societies pursue a thin body. Among the multiple reasons to lose weight, concerns about social perceptions play a prominent role in the desire to shed pounds. Previous research associates thinness with attractiveness, especially in Western societies. The current work demonstrates that moderate deviations from the average body size cue judgments on person perception dimensions. Results from three studies show that whereas moderately thin (vs. heavy) individuals are rated as more competent, moderately heavy (vs. thin) people are rated as more warm. The studies present mediation- and manipulation-based evidence that these effects occur because a thin (vs. heavy) body signals self-control—a construct instrumental in drawing competence inferences—and that a heavy (vs. thin) body signals emotional expressiveness—a construct that triggers inferences of warmth.