Researchers link income, exercise and breakfast to childhood obesity
By Michelle Osmond
Income levels and eating breakfast are just two factors that determine if a child will be obese. This comes from a recent report released by Dr. Wendy Young, Memorial's Canada Research Chair in Healthy Aging.
Dr. Young and her team recently studied a large population of Grade 7 children in Halton, Ont. They looked at the association between body mass index (BMI) and modifiable individual-level risks (such as physical activity and nutrition); modifiable environmental risks (such as environments that are human modified, including homes, schools, workplaces and location of physical activity and nutritional environments); and neighbourhood education levels.
"If you look at the federal government's national dialogue on healthy weights the ministers of health have just launched [Our Health Our Future: A National Dialogue on Healthy Weights], this kind of research is essential to the dialogue they're inviting on actions we need to take to ensure healthy weights for Canadians," said Dr. Young. "They see this kind of dialogue as a key step in curbing childhood obesity."
With funding from the Canadian Institutes of Health Research, Dr. Young wrote the report after the Region of Halton decided to take action to reduce childhood obesity, which according to researchers is now an epidemic.
Halton started to plan changes to their environment such as developing walkable and bikeable communities and increasing the availability of healthy food choices. But they wanted to know if these changes would make a difference. If communities make it easier for children and their families to make healthy choices, would fewer people become obese? And which healthy choices matter the most? To answer these questions, they partnered with Dr. Young to better see how physical and nutritional environments affect healthy weights.
Using survey data from Halton's Our Kids Network collected in 2006, Dr. Young's team concluded that socio-economic status and an active lifestyle were still the most powerful predictors of healthy weight (poverty had a negative impact), while eating breakfast helped a child maintain a healthy weight and time spent in front of an electronic screen did not.
The most significant predictor of lower BMI levels in the Grade 7 children, however, was their active lifestyle score – a combined score of physical activity, lower screen time, and eating breakfast regardless of socio-economic status or the sex of the student.
However, students who lived in a walkable neighbourhood were not more likely to have an active lifestyle and students who lived close to a produce store were not more likely to eat fruits and vegetables, which was also not associated with BMI.
Dr. Young admits there are some limitations with this study. "Our measurements of the built environment are based on adult concepts that may not apply to children. For example, it's unlikely that increasing access to sidewalks to shopping, postal services, and legal services reflect destinations of 12-year-olds and would increase their physical activity," explained Dr. Young. "Walkability, or the way the environment facilitates getting places on foot, may be less important for children than playability. In addition, the data was self-reported so the children may not have accurately reported their height and weight, physical activity or fruit and vegetable consumption."
Dr. Young worked with Drs. Alvin Simms, geography, and Veeresh Gadag, mathematics and statistics, also from Memorial, several researchers from Halton, as well as Dr. Sara Kirk, Canada Research Chair from Dalhousie University.
To view the full report, please visit www.mun.ca/nursing/about_us/FINAL_REPORT_HALTON_July_2011.pdf.