Reducing salt use lowers blood pressure, cuts health costs: study

Cutting Canadians' salt intake in halfwould eliminate high blood pressure in one million people and save the health-care system hundreds of millions of dollars a year, researchers in British Columbia say.

In Tuesday's issue of the Canadian Journal of Cardiology, health sciences Prof. Michel Joffres of Simon Fraser University in Burnaby and his colleagues looked at the effects of dramatically cutting sodiumconsumption.

A quarter of adults, about five million Canadians, have hypertension, a major risk factor for stroke and heart attack. Hypertension also contributes to kidney failure and dementia, according to the World Health Organization.

In total, the national Canadian average for daily sodium intake registered at 3,092 milligrams, one-third more than the recommended limit, according to Statistics Canada. The leveldoes not include salt people add to their food.

Reducing sodium intake by an average of 1,840 milligrams a day would decrease hypertension by 20 per cent and save the cost of medication to control high blood pressure, the researchers said, based on their statistical analysis of data from clinical trials andhealth surveys of Canadians.

"It would reduce the high blood pressure by about one million people, and reduce[health-care costs] by more than $430 million a year," Joffres told CBC News.

Lower hypertension rates could prevent or postpone about 7,000 deaths in Canada each year, he added.

Food industry in talks to curb salt

The study's estimates do not include additional money that would be savedif fewer peopleusehospital emergency services for strokes and heart failure, said Dr. Norm Campbell, a co-author of the study at the University of Calgary and a spokesperson for the Heart and Stroke Foundation.

The team urged governments to talk to the food industry about further reducing sodium content in processed foods. About 80 per cent of the sodium Canadians eat comes from processed food or food prepared in restaurants, Campbell said.

Some Canadian food manufacturersare already offering low-sodium alternatives because consumers are demanding it.

"What we're seeing is a growth in demand for information about sodium levels," said Elizabeth Margles, a spokesperson forLoblaw in Toronto.

European approach

In Finland and the United Kingdom, manufacturers have gradually cut the salt content in packaged foods, and labels clearly spell out which products are high in sodium — an approach advocated by WHO.

"The Food Standards Agency, which is a government organization, has set voluntary targets for the maximum amount of salt that should be in certain food products," said Naomi Campbellof the Consensus Action on Salt and Health in London, England. "Many sectors of the food industry have been compliant."

Europeanresearchers said the salt reduction has led to lower blood pressure, fewer heart attacks andstrokes, and lives saved.

Canadian experts saidthe best approach here would be a gradual reduction in the salt put in processed foods sosalt-loving palates will be able to adjust.

But the study applies the benefits of a low sodium diet to the general population when studies show only 15 per cent of people at most are sensitive to salt, Dr. Sandy Logan, a hypertension researcher at Mount Sinai Hospital's Samuel Lunenfeld Research Institute in Toronto and a consultant for the salt industry, said in criticizing the analysis.

"A population strategy will not provide benefit to most in the community, and the issue of harm to the general population has never been adequately addressed," said Logan.

The study's authors assume reducing salt is risk free, although there is no proof, he added.