BU study links home and school environments to children’s BMIs

Dan Miller

Daniel Miller

A recent study by Boston University School of Social Work Assistant Professor Daniel Miller found that different characteristics of home and school environments were related to a child’s body mass index (BMI) in kindergarten and the rate of BMI growth until fifth grade.

Using growth curve modeling and a sample of approximately 11,400 children from the Early Childhood Longitudinal Study kindergarten cohort, the study investigates the role school and home environments play in the childhood obesity epidemic.

Miller’s research concluded that after controlling for a large number of socio-demographic variables, children’s overall activity levels, characteristics of schools, and the influence of early health, a number of different home and school factors were found to be significantly associated with a child’s BMI in kindergarten and the rate of change in BMI over time.

“Environmental factors are the root of the obesity epidemic,” Miller wrote. “The identification of the full set of environmental factors related to increases in BMI is an important task for current research.”

Children who watched more television, who had mothers who worked more often outside of the home, who ate more breakfasts and lunches at school, and who attended schools with gymnasiums rated as adequate by administrators had BMIs that grew at a significantly faster rate, suggesting increased risk for obesity.  Children who got more hours of sleep per night, who ate more lunches at school, and who attended schools with cafeterias and gymnasiums rated as adequate by school administrators had significantly lower levels of BMI in kindergarten.  Children who ate breakfasts more often with their families and spent more minutes in recess had BMIs that grew more slowly over time.

“Further research and policy efforts should continue to acknowledge the multi-etiological manner by which the environment can affect rates of child obesity,” Miller said.  “It is important [that we] pay attention to the multiple ways that children’s environments can promote or protect against obesity.  It may not be worthwhile just to focus only on one risk or protective factor.”

The paper, “Associations between the home and school environments and child body mass index,” appears in the March issue of Social Science & Medicine.