If you've been inside a grocery store in the past couple of years, you've probably noticed the trend in food manufacturers adding "Made with sea salt" to their product packaging. The claim shows up on a wide variety of foods - from organic whole grain pretzels, to mixed nuts, to "American deli cheese product."
Clearly the food industry has decided salt from the sea is a major selling point. But why? Is it better for us than plain old table salt?
"Sea salt gets a health halo（光环）, and people are using a lot more of it," said Alissa Rumsey, a registered dietitian at NY-Presbyterian/Weill Cornell Medical Center. "The most significant difference is the texture."
Sea salts are coarser（粗糙的） and grainier（粒状的） than table salt because the former undergo less processing than the latter, Rumsey said. Sea salts are made from evaporated sea water. Table salt, on the other hand, usually comes from underground salt mines and is processed into finer crystals. (Fun fact: If you're a sea salt fanatic and are confident your local seawaters aren't polluted, you can make your own.)
The less-processed aspect of sea salt may be appealing, but both types of salt have the same basic nutritional value, Rumsey said.
"With some foods, less processing does equal healthier," like whole grains versus refined grains, she said. "But I wouldn't say sea salt is healthier than table salt.
"A teaspoon of table salt is finer, so it has more sodium by volume. But technically by weight they contain the same percentage of sodium -- about 40 percent."
Table salt is usually fortified with iodine, a practice that's been around since the early 20th century.
Sea salt may retain some other minerals depending on the water source - but generally not enough to make a difference in your diet.
"Sea salt does have a small amount of trace minerals, but it's really too small to offer much benefit," Rumsey said. "We get those minerals in other forms from our food."
One thing sea salt doesn't have is added iodine（碘）, which you'll often see noted on its label. Table salt has been fortified with iodine since the early 20th century as a way to get more of the essential mineral into Americans' diets. These days, Rumsey said, most Americans get plenty of iodine in their diets -- so you shouldn't worry about using sea salt instead if you like its texture and crunch.
The most important thing to remember: Sea salt is still salt, and you shouldn't consume too much of it.
"I tell people that whatever salt you do decide to use, to do so sparingly," Rumsey said -- and that goes for the sodium content in packaged foods, too. Aim for less than 2300 mg, or less than 1500 mg if you are over age 51 or have health concerns such as high blood pressure, diabetes or kidney disease.