Are diets low in sodium essential for everyone?
Excessive sodium consumption is putting the world’s health at risk, and placing a large burden on health systems, warns a new study. It is estimated that 1.65 million deaths from cardiovascular disease each year are linked to consuming too much salt on a regular basis.
“That’s remarkably high, that’s almost 1 in 10 of all cardiovascular deaths around the world,” Dariush Mozaffarian, study author told NPR.
“This suggests that a single factor in the diet [salt] could be contributing to almost 10 percent of the cardiovascular burden.”
This latest study adds weight to the argument that everyone should have a diet low in sodium, something many people ignore. Worldwide we consume on average, around 3,950 milligrams of salt per day. Although there are regional daily differences ranging from 2,000 to 5,500 milligrams, the global average is still nearly double what the World Health Organisation recommends (<2,000mg/day).
The study found the areas where the most heart attack and stroke deaths are linked to sodium, varies quite a bit. In Canada, the United States, Australia, and New Zealand around 10 percent of cardiovascular deaths can be attributed to salt intake.
Interestingly there is a wide-band stretching from Eastern Europe to Central and East Asia where the percentage of sodium attributable deaths jumps to 20-25 percent. The study authors put this down to the centuries old trade routes that link the continents.
“What seems to be linking those countries [in this band] … is that this is the Old Silk Road [trade] route, where people traveled many distances and needed salt to preserve their food,” says Mozaffarian. Centuries later, this tradition of eating salt-preserved foods remains strong.
A diet high in sodium can cause high blood pressure, which in turn raises the risk of a heart attack or stroke. While sodium occurs naturally in many foods such as milk and eggs, it is found in much higher levels in processed foods and it is these people are being warned to cut down on.
There is some disagreement over whether low-salt guidelines are beneficial for everyone. Another study, also published in the New England Journal of Medicine, said the risks associated with high salt consumption are increased in people with elevated blood pressure. It goes on to suggest that people with a healthy blood pressure can have as much as 3,500 milligrams of sodium a day, the typical amount Americans consume.
Image: Kosher salt by stlbites (CC BY-ND 2.0)