Yes, it’s still controversial, but it looks like (according to The Guardian‘s reporting) that successfully lowering your salt intake might – oops – increase your risk of heart attack after all:
The study by Prof Andrew Mente from the Population Health Research Institute of Hamilton Health Sciences and McMaster University and colleagues is large, involving more than 90,000 people in more than 300 communities in 18 countries. But it immediately reignited a simmering row with other scientists who are on a crusade to reduce our salt consumption to near zero.
Mente and colleagues found that the harmful effects of sodium – raised blood pressure and stroke – only occurred in countries like China, where the liberal use of soy sauce leads to sodium levels over 5g a day, the equivalent of 12g of salt. And they found that very low levels of salt actually led to more heart attacks and deaths, suggesting moderate salt intake may be protective.
“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,” said Mente.
The new study measured potassium as well as sodium levels in people’s urine and found that higher potassium, which is found in fruit and vegetables, cut rates of stroke, heart disease and death. “Perhaps salt-reduction evangelists and salt-addition libertarians could temporarily put aside their vitriol and support the hypothesis that diets rich in potassium confer substantially greater health benefits than aggressive sodium reduction,” they write.
The researchers’ peer-reviewed article is here, in Lancet