TORONTO — Ottawa should be more involved in fighting childhood obesity rather than having the provinces take action by forcing restaurants and schools to post calorie counts on menus, Premier Dalton McGuinty said Wednesday.

Obesity is a problem across Canada, and the federal government should take a closer look at what doctors are recommending to fight it, he said.

"The whole issue of childhood obesity -- it's not an Ontario issue," he said.

"I've spoken with other premiers about this. This is an issue that affects all the provinces and all the territories, and I'd love to see some federal leadership in this regard."

McGuinty was responding to the Ontario Medical Association's calls for the province to enact legislation that would see calories listed on menus in restaurants and school cafeterias.

That would allow both adults and children to make healthier choices about what they're eating, the doctors group said.

It also wants a wide-ranging education program to tell consumers and students what constitutes a healthy daily caloric intake.

One in four Canadian children are considered overweight or obese, and three-quarters of obese kids grow up to become obese adults, according to the OMA.

McGuinty said the proposal is "an idea worth considering," but it's up to Ottawa to take the lead.

"I don't know if that's the best way to do it, but I do agree that we need to do more to help Ontarians make informed decisions when it comes to their diet," he said.

The premier has a responsibility to take action because obesity is taxing Ontario's health-care system, said NDP health critic France Gelinas, who has tabled a private member's bill on the issue.

"Last time I checked, health care is the responsibility of the province," she said.

"This epidemic of obesity is having a tremendous effect on our society, on people's lives and on our health-care system, and something has to be done to address it."

Her bill, to be debated Thursday, would require food-service premises with annual revenues beyond $5 million to disclose calories in foods and drinks and to limit trans fat in menu items.

OMA president Dr. Ken Arnold has spoken favourably of a Canada-wide system for listing calories, but says he's not aware of other provinces or territories taking similar action.

In New York City, restaurant chains with more than 15 locations nationally are required by law to list calories on menus and menu boards, he said.

A similar law has been passed in California, and a bill before the U.S. Congress would make such calorie counting mandatory across the country.