Since December 1, a new regulation in New York requires chain restaurants to display a symbol, a salt shaker inside a triangle, on menu items that contain more than the recommended federal daily limit on sodium.
The city's Board of Health says the labels will save lives amid an epidemic of heart attacks and stroke for New Yorkers. Cardiovascular disease is a leading cause of death in the city, accounting for 17,000 deaths in 2013.
A 2010 study showed that New Yorkers consume an average of over 3,200 milligrams sodium every day, well beyond the recommended threshold of 2,300. The health department says daily salt intake is even higher among Hispanics and African Americans.
The label's main opponent, the National Restaurant Association, says the rule impinges on a restaurant's free speech by forcing them to display the information. This defense is the basis of many arguments against labeling movements across the country.
The city's health department responded to a lawsuit from the restaurant association, with health commissioner Mary Bassett saying in a release that the department is "disappointed that the National Restaurant Association would want to prevent New Yorkers from receiving this important health warning."
A judge is slated to consider the case on January 19.
The decision could quash other health label moves in the city.
New York has been a leader in pushing calorie counts, a ban on trans fats and other public health legislation, which have served as models for similar efforts around the country.