A mother's stress may contribute to her young children being overweight in low income households with sufficient food, according to a new Iowa State University study published in the September issue of Pediatrics, the professional journal of the American Academy of Pediatrics.
The study analyzed data collected from 841 children in 425 households in the 1999-2002 National Health and Nutrition Examination Survey.
Iowa State faculty members Steve Garasky, a professor of human development and family studies; Brenda Lohman, an assistant professor of human development and family studies; and Susan Stewart, an associate professor of sociology, all collaborated on the study. Lead researcher Craig Gundersen, a member of the agricultural and consumer economics faculty at the University of Illinois; and Joey Eisenmann, a member of the kinesiology and pediatrics faculty at Michigan State University, were also previous ISU faculty members on the research team.
The researchers used mothers' responses to interview questions to determine their mental, physical, financial and family structure levels of stress -- producing a cumulative stress index. The child's weight status was determined by their Body Mass Index (BMI), age and sex. Subjects were also broken into two age groups: three to 10 and 11 to 17 years of age. Household food insecurity status -- whether or not there is enough food to sustain healthy, active lifestyles for all household members -- was also measured from the mothers' interview responses.
In households with no maternal stress, low-income children in food secure households had a 33.0 percent probability of being overweight, while those in food insecure households had a 34.8 percent probability. As maternal stress levels increased, the probability of becoming overweight increased in children from food secure households, but decreased among those in food insecure households. When the maternal stress was found to be at twice the average level of the study sample, children in food-secure households had a 43.7 percent greater probability of being overweight or obese when compared with children in food insecure households.
"We were not able to observe what people are eating in these data. That's definitely part of future work," Garasky said. "But at this point we have to conclude that in stressful environments, children in households with adequate food -- maybe it is 'comfort food,' or maybe it's just larger quantities of more traditional food -- are possibly acting on the desire to eat more, and maybe even eat differently, than those from food insecure households."
For children over the age of 10, the relationship between household stress, food security and weight was found to be statistically insignificant -- meaning it was young children who were most affected.