Preschoolers who entered Head Start overweight or obese had achieved a healthier weight status than children in a comparison groups by the time they entered kindergarten, according to new research from the University of Michigan.

The research, published in the journal Pediatrics, found preschool-aged children who entered Head Start with an unhealthy weight status experienced a significantly healthier body mass index (BMI) by kindergarten age than children in comparison groups being seen for pediatric well-child checks. Obese and overweight children had a slowing of excessive weight gain while underweight children had a needed increase in rate of weight gain.

The comparison groups included children in a primary care health system, which included those receiving and not receiving Medicaid.

"The study findings suggest that participating in Head Start may be one effective strategy for obesity prevention and treatment," says lead author Julie Lumeng, M.D., of the University of Michigan's C.S. Mott Children's Hospital.

"Head Start programming is often at risk for cuts in funding. But at the same time, policymakers are looking for programs that can reach large numbers of American children to prevent obesity. We found that Head Start participation could help -- it is associated with robust, early and sustained beneficial changes in children's BMI."

Lumeng and her colleagues studied the weights and heights of 19,023 children attending Head Start in Michigan and compared their growth with children in the same age range who were seen in doctor's offices for checkups (the comparison group).

Head Start, a federally funded preschool program for low-income U.S. children, has been reported to have beneficial effects on developmental outcomes. But this is the first time the association with children's BMIs has been studied, says Lumeng, who is an associate professor of pediatrics at the U-M Medical School.

Lumeng says there are several features of Head Start that could be positively influencing children's BMIs. The federally regulated quality of meals and snacks provided at Head Start may be higher than that in many children's homes or in other child care facilities that do not have to meet federal meal standards.

Children may have more opportunities for physical activity and less sedentary time in Head Start than at home or in other settings, Lumeng says. Head Start may also provide needed structure to children's days that helps solidify routines and sleep patterns, both of which are associated with reduced obesity risk. Head Start might also reduce stress in families' households, giving them more financial and psychological resources to create a healthy environment at home.

Lumeng says these data indicate there's another resource to help reduce rates of obesity in children.

"The individual parent or pediatrician might consider enrolling the overweight or obese child in Head Start as part of an obesity prevention or treatment plan. For policy makers looking for programs to support in order to achieve reduced prevalence of obesity and overweight in American preschoolers, Head Start may be one such program," says Lumeng.