Pinch of salt may be too little, new research finds

Taking anything with a pinch of salt is usually a good approach, but not if that pinch is too little, it seems. New research has found that insufficient salt intake is not good for the health, though excessive consumption is also still risky.

Two reports from a global collaborative study published in the New England Journal of Medicine have concluded that salt has its "sweet spot".

Current intake of sodium is typically between 3.5 and 4 grams per day and some guidelines have recommended reducing sodium intake to below 2.3 grams per day, said NUI Galway professor of translational medicine Martin O'Donnell, who participated in the Prospective Urban and Rural Epidemiological (Pure) study. He said less than 5 per cent of the population is believed to adhere to the lower recommended consumption.

However, the research suggests the current “generally recommended healthy daily ceiling” for salt consumption is set too low.

The study, which was led by investigators from the Population Health Research Institute (PHRI), McMaster University and Hamilton Health Sciences, tracked consumption by more than 100,000 people for nearly four years.

It assessed sodium and potassium intake, and related both to blood pressure, heart disease, strokes and fatal illness. “Low sodium intake does reduce blood pressure modestly, compared to moderate (or average) intake, but low sodium intake also has other effects, including elevations of certain hormones that are associated with an increase in risk of death and cardiovascular diseases,” Prof O’Donnell says.

“In the Pure study, we found the lowest risk of death and cardiovascular events in those who consumed moderate amounts of sodium intake (3 to 6 grams per day), with an increased risk above and below that range,” he said.

The findings should not encourage complacency, he says, as high salt intake is a health risk, particularly for people with high blood pressure. Processed foods, bread, sauces, sausages and food prepared in restaurants may all have hidden salt levels, he explains, in contrast to fresh food prepared at home.

“The bottom line is that one to two teaspoons of salt daily is sufficient, but that may already be in food you are eating,” he said.