A study in the February 2007 issue of the American Journal of Public Health found over a third of the nation's low-income three-year-olds are overweight. The study, funded by the National Institute of Health and the Robert Wood Johnson Foundation, indicates Hispanic children are at the greatest risk.

This study was one of the first to look at the weights of toddlers. Other research has determined that 21% of American children over age five years are overweight - double the percent in 1971.

Drs. Rachel Timbro, Jeanne Brooks-Gunn and Sara McLanahan recorded the heights and weights of over 2800 children from 20 cities at ages birth, one year and three years. By age three, 44% of the Hispanic children were either overweight or obese, compared to 32% of white and black children. If a mother was obese herself, her child's odds of being overweight doubled. Allowing a child to go to sleep with a bottle also increased the odds. However, breast-feeding for six months or longer protected a child from getting too fat.

Factors that may have mattered did not. For instance, how much television a child watched or whether or not a child was in day care or cared at home by a parent did not increase or decrease his or her chances of overweight. Almost a fourth of the children in the study watched five or more hours of television per day.

The authors suspect that Hispanic mothers are more likely to pressure their children to eat too much because of a cultural belief that chubby children are healthier than thin ones.