Canadians have long been told that the packaged and fast food they’re eating contains FAR too much salt. Now, a new study has found the sodium levels in well-known sit-down restaurants are sky-high as well -- even in the foods most of us would assume to be healthy.

In a study published in the Canadian Journal of Public Health, researchers reviewed more than 4,000 food items sold in fast-food restaurants and popular sit-down restaurant chains. Using nutrition information on the restaurants’ websites, they found that many restaurants foods had much more sodium that dieticians and health experts recommend.

On average, 40 per cent of sit-down restaurant menu items exceeded the daily recommended intake of sodium -- meaning they contained more than 1,500 mg of sodium -- while 13 per cent exceeded the upper limit of 2,300 mg.

Stir-fries were among the worst offenders, as were poutines and fries with toppings; nachos, tacos and burritos; and sandwiches and wraps. Even salads -- the ultimate health food, we’ve long been told -- had high levels of sodium, especially entree salads containing meat or seafood.

The findings might be surprising to those who think that sit-down restaurants, which tend to cook with fresh rather than pre-made ingredients, would be a healthier option.

Study author Mary L’Abbe, a researcher with the department of nutritional sciences at the University of Toronto, says the findings are important, considering that on any given day, about 21 per cent of Canadians eat something from a sit-down restaurant, cafeteria or other food venue.

“This is one of the first studies that actually looked at sit-down restaurants -- those restaurants with waiters and waitresses. Most of the publicity has been focused on sodium levels in fast food chain foods,” she told CTV News.

L’Abbe says in many cases, even a single item at these sit-down restaurants -- meaning just the meat, or just the side dish, or just the soup -- could contain a whole day’s worth of recommended sodium.

On average, a single item at a sit-down restaurant had about 1,400 mg of sodium. By comparison, a single item at fast-food restaurants tended to have lower sodium levels: around 1,000 mg per item, on average.

Once combined together -- a burger with fries, or fish with mashed potatoes, for example -- the total meal sometimes contained two or three days’ worth of sodium.

Many ailments including high blood pressure, heart disease and stroke are linked to a high-salt diet. Some studies suggested up to 20,000 hospitalizations from problems such as heart attacks, strokes and kidney problems could be prevented if the country’s sodium consumption were cut in half.

L’Abbe says while Canadians can get a pretty good idea how much sodium they’re taking in when they eat packaged foods, they’re often in the dark when it comes to the food consumed when they dine out.

“Unfortunately, when Canadians go out a restaurant or a fast-food chain, they have no way of knowing what the sodium levels are in those foods,” she said. “That’s one of the conclusions we made in this study: consumers actually need more information to help them make healthy choices when they eat outside the home.”

Dr. Norm Campbell, an expert in high blood pressure from the University of Calgary who was not involved in the study, says the findings are likely an underestimation of how much sodium diners take in, since they didn’t account for condiments, such as ketchup or salt used at the table.

He also notes that the study was based on nutritional info provided by the restaurants themselves, so it’s not clear if those were accurate estimations.

He says the bottom line is that Canadians are risking their health when they eat out and that’s it’s time for all restaurants to warn diners about items that are high in salt

Garth Whyte, the president and CEO of the Canadian Restaurant and Food Services Association, says while the study is accurate, it’s based on 2010 data. Whyte says a number of restaurants have since been working on lowering the sodium levels in some of their menu items.

He says his membership is committed to driving down sodium levels in foods.

“We’re working hard. It’s a number one priority and we’re part of the solution,” he said.

With a report from CTV’s medical specialist Avis Favaro and producer Elizabeth St. Philip