Every weekday, a CNNHealth expert doctor answers a viewer question. On Friday, it’s Dr. Melina Jampolis, a physician nutrition specialist.
Question asked by Kristan of Atlanta, Georgia
My sister and I were talking about salt. She has noticed that sea salt is currently being marketed as a healthy, or trendy, food additive, but can’t figure out if there’s any real science behind the marketing. Are nonsodium salts, like magnesium chloride and potassium chloride, any healthier than traditional sodium chloride? People with, say, high blood pressure are told to stick to low-sodium diets. But is it the sodium, or is it a different quality that causes the increased risk?
Hi Kristan. In light of the new dietary guidelines for Americans that came out this week recommending a reduction in sodium intake to less than 2,300 milligrams a day, and a further reduction in intake to 1,500 milligrams a day among persons who are 51 and older and those of any age who are African-American or have hypertension, diabetes or chronic kidney disease, I thought this was a good time to answer this question.
Lowering sodium helps lower blood pressure, one of the main risk factors for heart disease and stroke, because too much sodium intake leads to water retention, which stretches blood vessel walls, leading to high blood pressure. This is particularly important as people age and blood vessels become more stiff, leading to even further increases in blood pressure.
Sea salt is a less-processed form of sodium, which may contain trace amounts of minerals, but by weight contains the same amount of sodium. It has a coarser texture and is not as finely ground as table salt, so an equivalent serving size contains slightly less sodium due to the larger volume of the salt crystals (you get less per serving).
In addition, some people find that it has slightly more flavor, so they can get away with using less, which is always a good thing. While sea salt does contain minute amounts of iodine, it does not have iodine added as table salt does. Iodine deficiency is relatively uncommon in the United States, so this should not be a major concern for most people.
Salt substitutes usually contain potassium chloride, which does not raise blood pressure as sodium chloride (table salt) does. It should, however, be used with caution in those with kidney disease, heart failure or on blood pressure or heart medications that increase potassium levels.
A better option is to use herbs and spices to add flavor to your meals to keep salt intake down. Even more important, limit your intake of processed and prepared foods (grocery and restaurant) as these foods make up more than 70% of our daily salt intake, while added salt makes up only about 10% (the remainder comes from naturally occurring salt). To my knowledge, magnesium chloride is used to melt ice and snow on roads, not as an edible salt substitute.