Fast-food giants try to cut the 'guilty,' leave the 'pleasure'

Fast food surges through Alec Armbruster's veins. His father, an advertising expert, has consulted for McDonald's, while Alec, 18, has stuffed many of his teen years with a "once-every-three-days" Taco Bell habit -- heavy on the soft tacos. 

"If I go to Taco Bell, I skip all the healthy menu items because the other food is a lot better," said Armbruster, a college student in Sarasota, Fla. "I never read the calories on those things." 

His age, gender and large appetite are typical of the core demographic that drives the business of Taco Bell and most fast-food chains. But times are changing.

Last month Taco Bell rolled out a veggie-laced menu line, Cantina Bell, entering the fray with quick-serve rivals that have launched a new, nutritional arms race: trying to out-healthy one another.

McDonald's is touting its "under 400 calories" items, including the venerable Filet-O-Fish sandwich. Burger King has just added smoothies and salads to its menu. Wendy's is pitching a new mobile app that lets customers personalize meals based on the number of calories they choose.

"The new battleground is shifting from 'value' to 'better for you' options," said Nick Castaldo, senior vice president of marketing at Anthony's Coal Fired Pizza, an East Coast chain, and a lecturer at NOVA Southeastern University in Fort Lauderdale, Fla. Read More