Controversial Canadian study says salt isn’t damaging, but experts disagree

We’ve all been told to cut back on how much salt we consume, but a controversial new study suggests we shouldn’t cut out salt altogether.

In fact, the Canadian study, published in the Lancet medical journal this week, argued salt may not be as damaging as we had thought, and even suggested that cutting back on salt isn’t always necessary.

“Our study adds to growing evidence to suggest that, at moderate intake, sodium may have a beneficial role in cardiovascular health, but a potentially more harmful role when intake is very high or very low. This is the relationship we would expect for any essential nutrient and health. Our bodies need essential nutrients like sodium, but the question is how much,” author Andrew Mente of McMaster University told the Guardian.

His team noted in countries like Canada, the U.S. and the U.K., cutting out salt isn’t necessary, and salt was mostly harmful in countries like China where the cuisine was sodium-heavy.

READ MORE: Why you crave salt — and what you can do about it

But Mente’s work also received criticism. Critics pointed out the study (which collected data from more than 90,000 people in 18 countries), didn’t measure sodium in people’s urine. And in 2016, they wrote another study with similar results and backlash.

“These criticisms include the use of ill participants in the study, leading to reverse causality (i.e. those suffering with heart disease don’t eat much food, and consequently eat less salt, but it is the illness that leads to death rather than lower salt intake), and the use of spot urine measurements,” professor of cardiovascular medicine Graham MacGrego told the Guardian.

Dietitian and blogger Abbey Sharp of Abbey’s Kitchen said when we see studies that make controversial statements, it’s important to not let them dictate what you should and shouldn’t eat.

“These were not randomized controlled trials. … These were observational studies which means they looked at communities rather than individuals given specific experimental conditions,” she told Global News. “I don’t believe that cutting anything out in our diet is necessary. Some people with high blood pressure or a history of heart conditions may need to reduce their intake of salt, however cutting out whole foods is not always necessary.”

Tweet This Click to share quote on Twitter: "<span style="font-weight:400;">These were not randomized controlled trials. … These were observational studies which means they looked at communities rather than individuals given specific experimental conditions," she told Global News. "I don't believe that cutting anything out in our diet is necessary. Some people with high blood pressure or a history of heart conditions may need to reduce their intake of salt, however cutting out whole foods is not always necessary."</span>

READ MORE: If menus shared calories, sodium, would you make healthier choices?

How much salt are we eating?

Health Canada notes Canadians consume about 3,400 mg of sodium per day — about double the amount we actually need.

“I believe we do consume too much salt and it is found everywhere in our diet — the more processed a food is, the higher the salt content and we eat a lot of processed foods,” Sharp explained. “Sodium is an essential nutrient in salt, but we are consuming far too much and that is leading to high blood pressure in some.”

Registered dietitian Jessica Tong adds it’s not appropriate to generalize populations like the U.S. or Canada and says it is “pointless” to limit salt, as the study suggests.

“Eating patterns and lifestyles vary significantly from region to region. Populations that consume a lot of fast food, pre-packed meals and salty snacks can certainly try to make changes in order to lower their salt intake.”

When salt is needed

Sharp adds there are also plenty of healthy foods that contain salt — which is why eliminating salt isn’t wise.

“There are a ton of foods that naturally contain salt like celery, beets, carrots, meats,” she continued. “I would never suggest cutting out these foods because they contain a small amount of salt. I’m also not adverse to using salt at the table or in cooking. Generally the amount of salt in home cooked meals pales in comparison to the salt in processed foods.”

She agreed with the controversial study in that cutting out salt can be damaging. 

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“Salt carries several health benefits, so going without it means you may be missing out on important trace amounts of calcium, potassium, iron and zinc, which are essential minerals that act as important electrolytes in our body. While in excess, a high intake of salt can raise blood pressure and increase your risk of heart disease and stroke.”

The key, both said, is moderation, as well as cutting down on highly processed food full of excess salt.