As the Food and Drug Administration (FDA) finalizes guidelines for the restaurant industry to voluntarily reduce sodium levels on menus, some limited-service restaurants are already using a “stealth health” approach to sodium removal, choosing to keep the effort mostly under wraps.

Boston Market is one example of a brand that successfully slashed sodium levels without overtly telling customers. Beginning in 2010, the 458-unit fast casual cut back on sodium in some signature dishes; mashed potatoes now have 26 percent less sodium, chicken and stuffing 20 percent less, and gravy, 50 percent. Boston Market did not note these changes on the menu and did not make a public announcement about these reductions until early in 2014, when a press release detailed the reductions and reported that customers did not notice the recipe changes.

“We took a holistic approach to reducing sodium in more than a dozen menu items, and we continue to test more reductions,” says Sara Bittorf, senior vice president and chief brand officer of Boston Market.

The chain’s testing methods vary depending on how important the item is to the brand. Success is determined based on whether the reduced-sodium version of the dish tastes any different than the original.

“We didn’t start this process with a goal in mind. With all items, we started with a 10 percent reduction, and did taste tests,” Bittorf says. “In the same testing with our R&D team, we then moved to a 20 percent reduction, then 30.”

With really salty items, like tortilla soup, the sodium reductions reached 50 percent without affecting the flavor. With chicken, the most important menu item, Boston Market team members tested with more modest reductions in 2010 and decided that 20 percent was as low as they wanted to go, though they continue to test further reductions.

This item-by-item approach is painstaking and underscores why sodium reductions are going to challenge the restaurant industry, says Joy DuBost, senior director of nutrition at the National Restaurant Association (NRA).

“There’s no magic number for what amount of reduction begins to affect flavor,” DuBost says. “It’s highly dependent on what you’re working with. People need to take a tailored approach.”

Peter Kaye is ‎CMO at Minnetonka, Minnesota–based Nutek Food Science, which produces a naturally sourced potassium salt, Nutek Salt, that is often found in the same salt mines as sodium salt but has no sodium. Nutek works with foodservice clients to develop new recipes and formulations that reduce sodium by as much as 50 percent, Kaye says, without compromising taste, functionality, or affordability. Nutek’s R&D work has also found that there’s no “right” reduction level; most of its foodservice clients aim for at least 30 percent less sodium.

“Taste is paramount. You can’t compromise on that,” Kaye says. “With our potassium chloride salt, we can usually use a one-to-one ratio of traditional salt and our salt, so we are able to make the significant changes, not just the little 5–10 percent tweaks. Our goal is to get clients to reduce as aggressively as possible for better health and better taste.”

DuBost says it is important to consider not just how much sodium to reduce or in what items, but also how to get the job done. “There’s so much to consider: consumer acceptance, flavor, working with the supply chain, safety. You can’t just cut and hope for the best,” she says.

Like Boston Market, several operators have found that the “stealth health” approach is the way to go with reducing sodium. “We’ve seen that there is no need to raise red flags, and it is best to make reductions gradually, over time,” DuBost says.

Kaye also believes in the “stealth health” approach, noting that his foodservice clients do not promote salt reduction efforts because people still see “reduced/low/no” products as tasting inferior. “I hope people see it as value-added some day, but we aren’t there yet,” he says.

Consumer research reinforces the slow and steady approach. A study published in the London-based Public Health Nutrition in January 2012 indicates that emphasizing salt reduction on front-of-pack soup labels “can have a negative effect on taste perception and salt use.”

In addition, The NPD Group recently found that U.S. consumers are less concerned about their sodium intake than in the past. More than 60 percent of the U.S. is trying to cut back on sodium intake, but that’s down from 68 percent in 2010. Further, 39 percent of adults look for sodium content on nutrition labels, down from 41 percent in 2010.

Research conducted by Healthy Dining Finder and funded by the National Cancer Institute shows that modest salt reduction can actually improve flavor perception. Reducing the amounts of sodium in target ingredients and making no other changes to burgers, seafood, pasta, soups, and salads resulted in every lower-sodium menu item being rated as high as or higher than the original version in terms of flavor, according to a Healthy Dining press release.

“Avoid the power of suggestion,” Bittorf says. “At Boston Market, we made these changes without even telling the general managers what was coming. There was no leading information, and there was no change in consumer ratings based on feedback we get from our 800 number.”

She adds that there is no reason to remain silent on sodium reductions after the fact. The initiative helps Boston Market be known as a feel-good, wholesome place to eat, she says, and customers don’t feel tricked when they learn about the change.