For its part, Dunkin has historically done most of its business before 11 a.m. To attract more customers after that morning crush, it rolled out a lineup of deli-like sandwiches in 2012. The offerings are relatively compact so they can be easily eaten on the go, but most have north of 400 calories.
The chicken salad sandwich, which is served on a croissant, has 580 calories, according to Dunkin's website. The fried chicken sandwiches range from 590 calories to 660 calories, depending on the toppings. The Texas toast grilled cheese sandwiches have 510 calories, if you don't include ham or bacon. Even the tuna salad wrap, which sound healthier, has 520 calories.
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What exactly qualifies as a snack varies from person to person. But Lauri Boone, a registered dietitian, in the Rochester, New York, area, said people should think of snacks as a "small, satisfying portion of food that can help curb hunger or a craving between meals."
Some examples she gave were a handful of nuts and a piece of fruit, a small cup of yogurt, or a handful of trail mix. When asked whether a 500-calorie sandwich could be a snack, she said no.
"That is a meal," she said. "I can't think of a good example where I would recommend a 500-calorie snack."
Dunkin' does offer some lighter sandwiches, however. The turkey, cheddar and bacon sandwich has 440 calories and the chain recently introduced a grilled chicken flatbread sandwich that has 360 calories.
Travis noted that the chain's lighter "DDSmart" sandwiches that are under 400 calories have proved popular, a reflection of the growing interest in healthy eating.
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Dunkin' also said on Tuesday that it expects "modest increases in coffee prices" at its restaurants as the company reviews rising commodity costs with its franchises.
The statement, emailed to Reuters by a Dunkin' spokeswoman, comes after retail coffee trend setter J.M. Smucker raised the U.S. list price of the packaged Folgers and Dunkin' Donuts brands by an average of 9 percent last week. Kraft Food Group followed with a 10 percent increase to Maxwell House and Yuban.
The price hikes were made after arabica coffee futures on ICE Futures U.S. soared nearly 90 percent between January and April on production concerns after an unprecedented drought scorched top grower Brazil's arabica belt. Futures prices have since dropped more than 20 percent.
—By AP. Reuters contributed to this report.