The test by Pizza Hut comes as the chain fights to win back market share. Last year, Pizza Hut sales fell 2 percent at U.S. locations open at least a year. Domino's, by contrast, saw the figure rise 5.4 percent while Papa John's saw sales rise 4 percent in North America.
Darren Tristano, a restaurant analyst with industry tracker Technomic, noted that Pizza Hut may be suffering in part because it's the biggest player and has the most to lose at a time when the pizza business overall is seeing moderate growth of about 2 percent to 3 percent a year.
But he also noted that the chain has failed to "evolve its product," while Papa John's has played up its quality and Domino's improved its pizza. Pizza Hut is owned by Yum Brands, which also owns Taco Bell and KFC.
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Pizza Hut's test varies in the two markets. In Toledo, customers can create their own Skinny Slice pies with up to five toppings, with each slice having 300 calories or less. In West Palm Beach, customers can pick from one of six pre-determined pies, with each slice having 250 calories or less.
The Skinny Slice pies are intended as a lighter version of Pizza Hut's hand-tossed crusts; a plain slice of the regular hand-tossed pie has 300 calories, according to the chain's website. A slice of the pan pizza has 350 calories and a slice of the "Thin `N Crispy" has 260 calories.
Pizza Hut also rolled out "Fit n' Delicious" pies more than a decade ago that had even fewer calories than the new Skinny Slice pies by going lighter on toppings. If the test proves successful, the Skinny Slice pies would replace the Fit N' Delicious pies, which are still available on request, Terfehr said in an email.
Other pizza chains have tinkered with alternative crusts as well. Domino's introduced a gluten-free crust in 2012 that is still on the menu. During the Atkins craze, Domino's also tested a whole wheat crust but ultimately abandoned the idea.
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"It did not take us very long to learn that people did not want that from Domino's," said Chris Brandon, a Domino's spokesman.