If Canadians could cut their salt intake by half, we could eliminate high blood pressure in one million Canadians, double the number of Canadians with adequately controlled hypertension, and save the health-care system $430 million a year.

That's according to a study by the Heart and Stroke Foundation and the Canadian Stroke Network, and published in the May issue of Canadian Journal of Cardiology.

The study is the first to investigate the contribution that excess consumption of dietary salt is making to the development of hypertension in Canadians.

It is estimated that one in four adults has high blood pressure. As well, nine of 10 Canadians who live to age 80 will develop the condition. High blood pressure is considered a major risk factor for stroke and heart attack.

The Heart and Stroke Foundations says that roughly 80 per cent of the sodium that Canadians consume comes from processed foods or food prepared in restaurants.

The salt people add to their food at the table makes up between 10 to 20 per cent of sodium intake.

Recently released Statistics Canada data suggest Canadians consume, on average, nearly 3,100 milligrams of salt a day -- about two teaspoons a day. That level is about 35 per cent higher than "tolerable upper intake level" and is more than twice what is considered necessary for health purposes.

Even young children consume too much. Children aged one to three averaged close to 2,000 mg a day. In this age group, 77 per cent of children exceeded the recommended daily limit.

Dr. Norm Campbell of the University of Calgary, one of the authors of the Heart and Stroke Foundation report, suggests that a reduction of 1,840 mg a day would cut doctor visits for high blood pressure and laboratory costs by 6.5 per cent.

As well, 23 per cent of people currently diagnosed with hypertension would no longer need medication.

"Canadians are unwittingly consuming far more than the Tolerable Upper Intake Level of sodium," Campbell says. "Reducing sodium additives to food is an excellent way to significantly improve the health of Canadians and reduce health costs."

But not everybody agrees with Campbell's conclusions.

Dr. Sandy Logan, a hypertension researcher at Mount Sinai Hospital's Samuel Lunenfeld Research Institute in Toronto, says that the benefit of a low-sodium diet may not have the population-based impact the study suggests.

In an interview with The Canadian Press, he notes that 50 per cent of those with hypertension do not respond to dietary salt restriction. He says studies indicate that only 10 per cent to 15 per cent of the general population is salt-sensitive.

As for reducing the amount of salt in Canadians' diets, Campbell says talks are already underway between hypertension researchers, Health Canada and some representatives of the food processing sector to reduce the sodium content of packaged foods.

The Heart and Stroke Foundation is helping to bring about change by having its Heart Check program endorse products with lower salt. One of its success stories, it says, is Campbell's line of Low Sodium soups.

"There were millions of tons of salt taken out of the Canadian diet... and they were able to do that with one product line," says the Foundation's Stephen Samis.

Ways to reduce your salt intake, from the Heart and Stroke Foundation 

Cut down on prepared foods and cook from scratch
Make your own soups, casseroles and sauces rather than using commercially prepared or canned varieties.

Make your own dressings
Salad dressings, ketchup, mayonnaise, and spreads all contain loads of sodium. Make salad dressings from healthy unsaturated oils (olive, canola, soybean), vinegar, and crushed garlic.

Go tropical
Use fruit salsas for meat, chicken or fish by creating mixtures of orange, pineapple, mango or other tropical fruit.

Read the nutrition facts table
On packaged and processed foods, look for lower-salt varieties whenever possible -- no more than 480 mg per serving or 960 mg per serving for entrees. In the ingredients list, watch out for other forms of sodium under these names: monosodium glutamate (MSG), baking soda, baking powder, disodium phosphate and any compounds that have "sodium" in its name.

Avoid using commercially softened water for drinking or cooking

Look for the Health Check™ symbol on foods
Health Check is the Heart and Stroke Foundation's food information program, based on Canada's Food Guide to Healthy Living.