And once a reformulated food passes the test, companies often avoid saying anything on the label or in advertisements about the nutritional improvements — especially when it comes to salt. Most people don’t think they need to cut back on sodium. Better to say nothing. It's known in the trade as "stealth health."

Together, the two came up with Bloomfield Hills-based Vita Perk, a powdered coffee supplement with 15 vitamins and minerals packaged in a thin, single-serving pouch. As Kifferstein said: "While people may often forget to take a vitamin, or even dislike swallowing one, they never forget their morning coffee." "Stealth health" is a growing trend in the food industry, according to Darren Tristan, executive vice president of Technomic, a Chicago-based food research and consulting firm.

Food and restaurant companies are under increasing pressure to make products healthier, but sometimes they don't want customers to know when they have cut the salt or fat. Companies have employed the tactic, which some executives call "stealth health," in tweaking products including Hamburger Helper, Oreo cookies and McDonald's french fries.

Sara Lee is hoping for more breakout products such as its Soft & Smooth bread with a "stealth health" combination of white bread made with whole grain.