Depending on which drink is selected, McDonald's says the Happy Meals with Fish McBites have between 385 calories and 415 calories.
McDonald's, often a target for health advocacy groups that say Happy Meals encourage kids to eat junk food, in 2011 began adding apple slices and reduced the portion of French fries in the meal boxes.
For adults, the Fish McBites will come with tartar sauce and be served in cartons that make them easy to share or eat as a snack on the go, which Irwin said is an important attraction for customers.
"It fits in your cup holder in the car," he said.
The big question is whether they can boost sales in the months ahead. In the last quarter of 2012, McDonald's managed to eke out a higher profit in part by touting its Dollar Menu and urging franchisees to stay open on Christmas. But for January, the company warned that a key sales figure is expected to fall again. That would follow a drop in October, which was the first decline in the monthly figure after nearly a decade.
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