Ontario's new law forcing large restaurant chains to show calorie counts on their menu is an important step toward encouraging better health, according to one weight management expert, but it's not going to cause massive change on its own.

As of Jan. 1, all restaurants with 20 or more locations in Ontario will have to display how many calories each of their food and drink items have on the menu.

Dr. Yoni Freedhoff called it an important and necessary step in the right direction that will probably be copied in other provinces, but not enough to drive mass change on its own.

"The likelihood of this single change having a dramatic impact on diet-related chronic disease incidence in Canada is low, but that doesn't mean it's not an important thing to do," he said in an interview Tuesday.

"It's like looking at a particular sandbag in a levee and asking 'Will that one sand bag stop this flood?' Of course the answer is no but of course, we also need those sandbags."

Dr. Yoni Freedhoff

Yoni Freedhoff says posting calories on menus is a step in the right direction but only a small part of solving the problem. (CBC)

Dr. Freedhoff said research in other areas that have calorie labels on menus has shown it's most effective to people who already watch their calories.

He suggested tackling how companies are able to advertise to children and what they can claim about nutrition on the front of their packages as some next steps for governments.

"Our job is to provide people with environments that encourage and enable and make healthier choices easier, rather than create environments make people feel guilty about less healthy choices," he said.

Federal Health Minister Jane Philpott said in October the department will be overhauling the country's food marketing and labelling rules.

Changes not ruffling many local feathers

The new menus didn't see much resistance on a rainy back-to-work Tuesday morning in Ottawa.

"I do try to look at the menu and try to see what the healthier option is," said Neha Beri.

"Obviously sometimes it's a matter of what's practical for the day, if I need to grab something quick, but at least it could be the lesser of two evils depending on calorie count."

"We're not the kind of people that looks [calorie information] up so I think it's beneficial to have it kind of in-your-face," said Kelly Caldwell. 

"Pamphlets are a waste of paper and you're not going to look it up on the internet when you're getting fast food."

The new menu rules have been criticized for their cost to restaurants and potential harm for people living with some kinds of eating disorders.