Finally some headway in the fight against childhood obesity. For the first time in nearly three decades, the epidemic may be leveling off. Last May, a study published in the Journal of the American Medical Association found that the prevalence of overweight and obese kids in the 6-to-11-year-old age group appeared to have hit a plateau of about 32% from 1999 to 2006. Experts say that the leveling off may be due not to better diet and exercise but to the possibility that we've hit a sort of genetic ceiling, with the entire population of children susceptible to gaining too much weight having done so.