The Lancet published a peer-reviewed medical study based on data from over 130,000 individuals. The study compared salt intake to risk of death and risk of heart attacks (and other cardiovascular events) in people with and without high blood pressure. Here’s a summary of the study in a news article.
1. high salt intake increases the risks of death and of cardiovascular events in persons who have high blood pressure, but NOT in persons with normal blood pressure,
2. low salt intake increases the same risks, regardless of whether your blood pressure is normal or high.
The study authors opined: “These data suggest that lowering sodium intake is best targeted at populations with hypertension who consume high sodium diets.”
What does this mean? If you have high blood pressure, too little salt is bad for you, and too much salt is bad for you. If you do not have high blood pressure, too much salt is not so bad (within limits), but too little salt is still unhealthy. And this makes sense, since salt, that is to say, both sodium and chloride, are essential nutrients. They are electrolytes, needed in the blood and tissues of the human body. In the study, 4 to 5 grams of salt per day (about 3/4 of one teaspoon of salt) was considered optimal, while any intake below 3 grams of salt per day (about 1/2 teaspoon of salt) was considered low and showed increased health risks. An intake of about 7 g/day (about 1 and 1/4 teaspoons of salt) was high.
Salt intake is NaCl (sodium and chloride). Sodium intake is 40% of salt intake. So 3 g/d of table salt will provide the minimum for both sodium and chloride (1.2 + 1.8 = 3.0).
The study authors included a dozen researchers with PhDs and ten physicians with MDs. And the article was approved after a peer-review process, in world-renowned medical journal The Lancet. But the conclusions of the study have been called into question and ultimately rejected by many persons. Why? One reason may be that this conclusion flies in the face of the cultural assumption that salt is bad for you.
Another reason may be the fact that the typical American (or we could say Western) diet is too high in salt, which results in more persons with high blood pressure in the population. Health authorities like the WHO and the CDC would like to see lower salt intake, because they are looking at the problems caused by excess intake. But perhaps they have failed to give enough consideration to the health problems associated with low intake of this essential nutrient.