More than one in five teenagers have at least one risk factor for heart disease, such as obesity and high cholesterol, finds disturbing new research that suggests heart health messages aren't getting through to teens.

According to statistics being released at the Canadian Cardiovascular Congress in Edmonton, the number of Grade 9 students who have one or more cardiovascular risk factors has risen to 21 per cent in 2008 from 17 per cent just six years before.

The number of obese teens has risen from 11 per cent to 13 per cent, while the rates of those with elevated cholesterol have almost doubled from nine per cent to 16 per cent.

The only figure to buck the trend has been the number of students with high blood pressure, which dropped slightly from 19 per cent to 17 per cent.

The statistics were compiled by evaluating the heart health of 20,719 students who entered Grade 9 between 2002 and 2008. Researchers assessed the students' blood pressure as well as their blood cholesterol, and measured their height and weight.

While the students evaluated were from the Niagara region of Ontario, the figures mirror what's going on in all of Canada, believes Dr. Brian McCrindle, a pediatric cardiologist at The Hospital for Sick Children in Toronto.

"This study is further evidence of an accelerating decline in the heart health of Canada's teens," McCrindle said in a statement released by the Heart and Stroke Foundation, which is co-hosting the Edmonton conference.

"Children shouldn't have these profiles."

McCrindle says what is most worrying about the numbers is that it is well known that at least three-quarters of teens who are overweight or obese will stay that way for most of their lives. That will put them at the highest risk for heart attacks and strokes in adulthood.

"What needs to be brought to bear within the public realm is that the origins of heart disease in adults actually begin in youth, and it begins in youth with the accumulation of these risk factors."

Heart and Stroke Foundation spokesperson Dr. Beth Abramson says it is shocking that one in five 14- and 15-year-olds has high blood pressure.

"What does this say for the future health of these young teens? They are at risk of developing long-term health effects such as premature heart disease and type 2 diabetes," she wondered in a news release.

She said she also found the spike in the teens' cholesterol levels disturbing.

"An increase of this magnitude in this age group is astonishing," she said. "These risk factor levels will continue to increase and track into adulthood unless we do something now. These children are in grave danger."

Most of the risk factors are connected to lifestyle, say the researchers. They say that despite public education campaigns about the importance of exercise, kids' behaviour doesn't seem to be changing.

The researchers found that only 22 per cent of the teens were physically active for 90 minutes at least five days a week - down from 28 per cent in 2002. As well, the number of kids reporting they spent 20 or more hours a week in front of a TV or video game console rose from 22 per cent in 2002 to 24 per cent in 2008.

"With changing technologies, we need to exercise our bodies more than our brains," said Abramson.

"Over 50 per cent of Canadian children between the ages of five and 17 aren't active enough to support optimal health and development - and over a quarter of our children and youth are overweight or obese."

Abramson says parents don't need to force their kids to add 90 minutes of exercise into their already busy days; "you simply need to encourage children to trade an hour of inactivity for an hour of activity," she says.

Dr. McCrindle notes that one of the great deficiencies in Canada is that, although there is a push for guidelines on how to manage heart health risk factors in adults, there is very little guidance for how to help kids.

"We need comprehensive and integrated Canadian guidelines for keeping our children healthy and we need them soon, because this type of study is showing the worst is yet to come," McCrindle said.

"This is the first generation of children that may have a shorter lifespan than their parents."

Abramson adds that it will take all levels of society to give children a healthier future.

Individuals, families, schools, communities, businesses, industry, and government collectively can play a role in improving the health of our youth - now and for the future," she says.

The data for the research were collected by Heart Niagara Inc., a non-profit corporation that partnered with Niagara-area school boards and public health officials in a Grade 9 physical education curriculum enrichment program designed to prevent chronic disease.