Children living in Canada's poorest neighbourhoods gained more weight over an eight-year period than those living in middle-income areas, a new study suggests.

The study, released Monday by Statistics Canada, tracked the body mass index of about 2,200 children who were assessed at two-year intervals from the ages of two and three, to 10 and 11 between 1994 and 2002. BMI is calculated by dividing weight in kilograms by height in metres squared.

In the poorest neighbourhoods, 40 per cent of children were overweight, the study suggests.
(CBC)

"What we found is that at age two and three we didn't see a big difference between neighbourhood income and overweight," researcher Lisa Oliver, a PhD candidate at Simon Fraser University in British Columbia and post-doctoral fellow at Statistics Canada, said from Ottawa.

"But by ages 10-11, we saw quite a large discrepancy between neighbourhood income and children's body weight."

In the poorest neighbourhoods, 40 per cent of children were overweight, Oliver said.

"Thirty per cent were overweight in the middle-income neighbourhoods, and in the richest neighbourhoods 27 per cent were overweight. So we see a clear gradient, increasing overweight in lower-income neighbourhoods."

More study on causes underway

The longitudinal study did not, however, look at aspects of the various neighbourhoods that might be influencing weight. Oliver has begun another study of eight neighbourhoods in the greater Vancouver area to try to understand more about this — "to actually look at physically what's in rich and poor neighbourhoods, and see if this differs."

Other studies have indicated that kids in low-income neighbourhoods are involved in fewer organized physical activities, she said, and that parents find there is a lack of safe parks and playgrounds for their children.

Diane Finegood, scientific director for the Canadian Institutes of Health Research, Institute of Nutrition, Metabolism and Diabetes, said there's a general recognition that lower socioeconomic status is associated with obesity in adults, so these findings related to children are not surprising.

"Some of the things that might put kids at a disadvantage would be aspects of their neighbourhood like safety, ability to walk to school," said Finegood, a professor at Simon Fraser University who was not involved in the research.

"High-energy expenditure activities like hockey and other kinds of sports like soccer may be less accessible to poor children, not only because they're …more expensive to participate in, but also because parents may have less availability to take their kids or to support their kids in doing these activities," she said from Vancouver.

"Access to an adequate healthy diet is also challenging for people living on a low income."

Ramona Josephson, a Vancouver dietitian, said that when people don't have enough time to plan and prepare meals, chances are they'll end up eating whatever's in front of them, rather than making good decisions.

"We are so surrounded by relatively inexpensive, very accessible fast foods," she said. "The key really is to try and encourage people to recognize that a little bit of planning can go a long way, not only in terms of the cost of the food, but in terms of what you're providing for your kids as well."

Josephson noted that the risk for chronic disease escalates for the obese.

"I think that would be wonderful if resources could be made available for health professionals to be working in these areas, because the challenges are different."