Temperamental factors associated with rapid weight gain and obesity in middle childhood.

Studies of the perplexing problem of childhood obesity have considered etiological factors in the child and environment, but have largely ignored the child's temperament or style of interaction with the environment. In this report, a significant relationship is demonstrated between temperament and both rapid weight gain and actual obesity in middle childhood. In a longitudinal study of 138 children, weight-for-height percentile gains between 4 to 5 years and 8 to 9 years were significantly correlated with eight of nine difficult temperament characteristics and with a cumulative "index of difficulty." A separate cross-sectional study of 21 obese (greater than or equal to the 95th percentile weight for height) 6- to 12-year-old children found them to be significantly less rhythmical/predictable and lower in persistence/attention span than matched controls. These normal behavioral style characteristics, interacting with metabolic, dietary, and environmental factors, may predispose some children to inappropriate eating habits or make it harder to maintain a dietary plan to remedy the problem.