The protective effect of these routines remained strong even after Anderson accounted for other factors that can contribute to childhood obesity, such as the mother's obesity and low family income. The findings suggest that adopting these routines can be a powerful way for families to encourage healthy weight in their children regardless of socioeconomic background, she says.

In addition, says Dr. David Ludwig, director of the Optimal Weight for Life Program at Children's Hospital Boston, the routines are relatively easy for most families to adopt. "This is a beautifully simple study. It makes a very important point, and one that needs to be re-emphasized time and again. These are all behaviors that are within the reach of us all."

The data Anderson used came from the Early Childhood Longitudinal Study Birth Cohort, a government-sponsored study of a cross section of children born in the U.S. in 2005. The children were enrolled in the study at birth; their parents answered questions about the children's daily routines -- including how much television they watched, when they went to bed each night and when they woke up each morning -- at 9 months, 2 years and 4 years.