Current maximum sodium recommendations are too low and could even be “unsafe,” according to a new pair of studies from hundreds of researchers including some from McMaster University and Hamilton Health Sciences.
While many healthy eating guidelines suggest people lower their sodium intake to 2,300 mg of sodium or less per day, the global studies have found that people are at risk of heart disease and other ailments when they consume too much or too little sodium.
Health Canada’s guidelines recommend those aged 14 to 50 consume 1,500 mg of sodium a day.
“We shouldn’t be focusing on restricting our sodium intake to really low levels,” said Andrew Mente, an associate professor of clinical epidemiology and biostatistics at McMaster University, who acknowledges that sodium is necessary for managing physiological functions, nerve processing and maintaining fluid levels.
Instead, he said, researchers from 18 countries who developed the studies have discovered that there is a “sweet spot” for salt intake — somewhere between 3,000 mg and 6,000 mg of sodium per day.
The good news, Mente said, is that most people consume between 3,500 and 4,000 mg of sodium a day, an amount within the range that the studies recommend as healthy.
To reach their conclusion, Mente said, researchers analyzed the sodium and potassium intake and blood pressure of more than 100,000 people with diverse health histories for nearly four years to determine their effects on deaths, heart disease and strokes.
The studies — funded by more than 50 organizations, including the Heart and Stroke Foundation and the Canadian Institutes of Health Research — uncovered that the relationship between sodium and blood pressure is “non-uniform.”
“If you eat a high salt diet then the relationship between sodium and blood pressure is strong and lowering your sodium will result in larger reductions of blood pressure,” said Mente.
“If you’re eating an average sodium diet, lowering your sodium intake further would only have modest effects on blood pressure.”
The studies also revealed that the effects of sodium on blood pressure can be most dramatic for the elderly, people with high blood pressure, those consuming more than 5,000 mg of sodium a day and those on a low-potassium diet.
To stay healthy, Mente recommends that people not be complacent about their sodium intake, but also be mindful of other factors that contribute to their health like eating fruits and vegetables.
“It’s more important to focus on eating an overall healthy diet, exercising and not smoking,” he said.