Forcing Ontario restaurants to display calorie counts on menus may have dangerous and unhealthy consequences for people with eating disorders, say experts.

The Healthy Menu Choices Act, which take effect Jan. 1, requires restaurants with 20 or more locations in Ontario to openly display calorie counts for items on their menu. 

Andrea LaMarre, a PhD candidate at the University of Guelph, launched an online petition several weeks ago in her bid to have the legislation repealed. Counting calories can be an obsession for someone struggling with an eating disorder, explained LaMarre, who focuses much of her research on young people with eating disorders.

"They may be able to more easily combat those thoughts that make calorie counting an obsession, if the number isn't directly thrown in their face every time they go to that restaurant," she said.

'It would have fed my eating-disorder mind'

Calorie Count

Health activists say food menu calorie counts can harm people with eating disorders, such as bulimia and anorexia. (Sonya Varma/CBC)

The act was designed to give people more information about the calories they're consuming when eating out so they can make healthier choices, but experts are concerned that posting the numbers can be a constant reminder to people struggling with eating disorders, such as bulimia or anorexia.

Posting calorie counts at restaurants would have been devastating for Lauren Benson, who started struggling with anorexia when she left Windsor, Ont. and headed to university in 2013.

She lost so much weight, she eventually weighed less than 90 pounds. Seeing lists of calorie counts on menus would have only encouraged her to monitor her food intake even more, she told CBC News.

"I would have loved it because it would have fed my eating-disorder mind," she said. "It brings up the calories and makes it more obvious."

Lauren Benson

Lauren Benson, who has struggled with an eating disorder, looks at before and after photos of herself. (Meg Roberts/CBC)

Dr. Sean Wharton, who specializes in weight management and diabetes, calls the new calorie labelling law "terrific," though he doesn't know how effective it will be.

"From an overall population level, I am not sure that this will have the big impact that we are actually looking for," he said.

The Hamilton doctor recognizes the studies that support the bill show a small decrease in calorie consumption, and those studies are based on small population sizes.

"The data is weak," Wharton said. "There is not a lot of data that really demonstrates there is a population decrease in weight or that the nutrition status of the population is actually better as a result of these labelling laws."

Not worth the risk

That lack of evidence is what concerns people like LaMarre. She criticizes the government for introducing the new rules, considering the harm it can cause people with eating disorders.

"Given the lack of strong evidence to support the actual enactment of calorie counts on menus, it's not really worth the risk of making life a lot more difficult with eating disorders," she said.

Even after seeing the number of calories people may still eat the restaurant food, only to compensate later by vomiting, over exercising or misusing substances like laxatives, said Leta Marchand, clinical manager at the Bulimia Anorexia Nervosa Association in Windsor, Ont.

"They're calorie counting every bite, every sip that goes into their body," she said. "Some of them have found it triggering for their own recovery process, making it difficult to make food choices."

Many restaurants have got a head start on the province's regulations and are already listing the amount of calories in their food.

At Costco, menu boards show a poutine contains 1,490 calories. A sausage breakfast sandwich on a biscuit at Tim Hortons comes in at 500 calories.