Newfoundlanders have long held the dubious distinction of being among the heaviest-set people in Canada.

On average, the province has the highest body mass index in the country, just ahead of the Northwest Territories, Nova Scotia and P.E.I., according to the most recent report by the Canadian Institute for Health Information.

And Dr. Huang Sun is in the belly of the beast, so to speak, to uncover the genetic mystery behind the disproportionate number of ample behinds.

"It's clear that obesity is caused not only by environmental factors, not only by what you eat and your physical activity levels," Sun, a geneticist at Memorial University in St. John's, said in a recent interview. "It also largely depends on your genes."

For that reason, it's the size of the Newfoundland's genes - not the size of its jeans - that makes it the perfect place for Sun's research.

Geographically isolated from the rest of Canada, Newfoundland has seen limited immigration. Most of the island's 500,000 residents can trace their ancestry to the original 20,000 settlers.

Within this small gene pool, Sun hopes he can find the secret to slim.

"Obesity has become epidemic in North America," Sun said, and other countries are quickly catching up. "We hope to find some basic genetic factors."

Sun is looking for "skinny genes," those that are more active in people who have less body fat. He estimates that's just 20 per cent of the population.

"The hypothesis is that some people easily gain weight and some people don't," he said.

Sun needed volunteers suspected of having the skinny gene and volunteers believed to be without it.

Around the campus, Sun has posted notices seeking two very different types of people.

So far, he has 550 volunteers.

Less than one year into the study, Sun said he's compiled some promising results.

Identifying such genetic triggers would allow doctors to diagnose a predisposition to obesity in childhood and take preventative measures.

But there is also the potential for more lucrative, applications.

North Americans spend hundreds of millions of dollars every year on diet books, medications, herbal supplements and anything else that promises to battle the bulge.

If researchers find a way to turn on the genetic skinny switch, they will certainly never go hungry again.

"Wouldn't that be wonderful," said Marlene Bayers, regional manager of Weight Watchers in Newfoundland and Labrador.

The more options available for people struggling with weight the better, she said.

Still, she is wary of any quick fixes.

"People really would love to have a shortcut, understandably," she said. But "behaviour still has to come into it."

Marc Tremblay is a professor of kinesiology at the University of Saskatchewan and one of the country's foremost experts on obesity.

"If we're looking for a quick fix or something over-the-counter that's going to resolve the fact that we're not living the way that we've evolved to live, I don't think those magic bullets are going to be easy to find," Tremblay said in a telephone interview.

Certainly there is a genetic element, he said.

But the fact that obesity has increased so dramatically in recent decades is a strong argument that more than a gene-fix is needed.

"Certainly the human genome hasn't morphed in such a period," Tremblay said.

Understanding the genetic cause of obesity has potential. Anything that helps reverse the huge problem has potential, he said.

Sun agrees that our environment is a big factor in the obesity epidemic, but we all live in the same environment.

"Some people eat what they like to eat and aren't overweight," he said. "Others exercise and eat right and are overweight."