Social norms in food intake among normal weight and overweight children.

This experimental study investigated whether children's food intake is influenced by a peer's intake directly and over time and whether this depends upon weight status. The study consisted of two sessions taking place at Dutch primary schools. During the first (social modeling) session, the participants (N=223) were asked to solve a puzzle with a same-sex normal weight confederate who was instructed to either eat nothing, a small or large amount. In the second session (about two days later), the participants had to solve the puzzle alone while they could freely eat. The study involved a three (no, low, high confederate intake) by two (normal weight, overweight) between-participants design. An interaction effect in the first session suggested that overweight children might be triggered to (over)eat when a peer eats a high amount of snack food, whereas the food intake of normal weight children seemed to depend on whether the confederate did actually eat, regardless of the amount. The guideline set during the first session persisted over time and influenced food intake during the second session, while differences between normal- and overweight children became insignificant. Peers can set an example as to what food intake is appropriate which could affect long-term food intake.