A registered nurse is sounding the nut allergy alarm over potentially confusing allergy labels on packaged foods.

While the red circle with a line through it is an internationally recognized symbol for ‘no,' the symbol with a line through a peanut doesn't necessarily mean no nuts.

Rob Cimaglia, who has a severe allergy to tree nuts, was shocked to discover that a package of granola bars he purchased at IGA had the no-nut symbol on the front, but contained almonds in the ingredient list.

"It's terrifying to think what could have happened had I not stopped and actually read the label," he said.

It turns out that the no peanut symbol simply means no peanuts, and tree nuts are a whole other matter. Rob wondered if he was the only one who was confused.

CTV's Lynda Steele took the no-peanut logo to the streets to see what other consumers thought.

One mother said that the shape of the peanut on the box is enough for her to believe the symbol actually meant no nuts altogether.

"It's terrible, they need to re-do it. It's not clear enough -- it has to be precise," she said.

Over 340,000 Canadians are allergic to tree nuts like walnuts, almonds, hazelnuts, coconut, cashews, pistachios and Brazil nuts.

The allergies are now one of the leading causes of fatal and near fatal reactions to food.

Natasha Subotic's son used to be allergic to peanuts and now she volunteers her time to educate others.

She admits there's a confusing and inconsistent array of allergy symbols and warnings when it comes to nuts. And while those symbols are a good start, Subotic says product packaging needs to be made more user-friendly.

"Ingredients lists are good on some products, on other products they're very small, so increasing the size of the letters would be a way to go for sure," she said.

Cimaglia would like to see one warning symbol that represents nuts of all kinds. Until then, he warns fellow consumers to read the label every single time.

"I'm shocked that there hasn't already been a fatality or a near miss because of this logo," he said.

New Canadian food labeling rules were introduced this spring. Health Canada says the new regulations will enhance labeling for food allergens, gluten sources and added sulphites. Manufacturers have until August of 2012 to comply with the new rules.

But some companies are going a little overboard when it comes to warning labels. Some brands are so worried about potentially being sued they're putting no-nut labels on things like fresh ground beef and apple juice.

To be safe, people with severe nut allergies should always read the ingredient list before eating packaged foods.

With a report from CTV British Columbia's Lynda Steele